Failed to write data to rbd device even removed from blacklist by MIZZ122 · Pull Request #20 · ceph/ceph-client

MIZZ122 · 2018-08-15T03:23:21Z

Map rbd to multiple nodes as the iscsi target and use multipath on iscsi initiator.path_grouping_policy is failover.The iscsi initiator sends data to the target. When the active path of is broken because the Internet problem, the data is switched to the alternate path. However, the original path is added to the blacklist. After the path is restored, the path is removed from the blacklist. , but the rbd device on the path failed to write data.

-m tracker.ceph.com/issues/25150

Crash dump shows following instructions crash> bt PID: 0 TASK: ffffffffbe412480 CPU: 0 COMMAND: "swapper/0" #0 [ffff891ee0003868] machine_kexec at ffffffffbd063ef1 #1 [ffff891ee00038c8] __crash_kexec at ffffffffbd12b6f2 #2 [ffff891ee0003998] crash_kexec at ffffffffbd12c84c #3 [ffff891ee00039b8] oops_end at ffffffffbd030f0a #4 [ffff891ee00039e0] no_context at ffffffffbd074643 #5 [ffff891ee0003a40] __bad_area_nosemaphore at ffffffffbd07496e #6 [ffff891ee0003a90] bad_area_nosemaphore at ffffffffbd074a64 #7 [ffff891ee0003aa0] __do_page_fault at ffffffffbd074b0a #8 [ffff891ee0003b18] do_page_fault at ffffffffbd074fc8 #9 [ffff891ee0003b50] page_fault at ffffffffbda01925 [exception RIP: qlt_schedule_sess_for_deletion+15] RIP: ffffffffc02e526f RSP: ffff891ee0003c08 RFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffffc0307847 RDX: 00000000000020e6 RSI: ffff891edbc377c8 RDI: 0000000000000000 RBP: ffff891ee0003c18 R8: ffffffffc02f0b20 R9: 0000000000000250 R10: 0000000000000258 R11: 000000000000b780 R12: ffff891ed9b43000 R13: 00000000000000f0 R14: 0000000000000006 R15: ffff891edbc377c8 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #10 [ffff891ee0003c20] qla2x00_fcport_event_handler at ffffffffc02853d3 [qla2xxx] #11 [ffff891ee0003cf0] __dta_qla24xx_async_gnl_sp_done_333 at ffffffffc0285a1d [qla2xxx] #12 [ffff891ee0003de8] qla24xx_process_response_queue at ffffffffc02a2eb5 [qla2xxx] #13 [ffff891ee0003e88] qla24xx_msix_rsp_q at ffffffffc02a5403 [qla2xxx] #14 [ffff891ee0003ec0] __handle_irq_event_percpu at ffffffffbd0f4c59 #15 [ffff891ee0003f10] handle_irq_event_percpu at ffffffffbd0f4e02 #16 [ffff891ee0003f40] handle_irq_event at ffffffffbd0f4e90 #17 [ffff891ee0003f68] handle_edge_irq at ffffffffbd0f8984 #18 [ffff891ee0003f88] handle_irq at ffffffffbd0305d5 #19 [ffff891ee0003fb8] do_IRQ at ffffffffbda02a18 --- <IRQ stack> --- #20 [ffffffffbe403d30] ret_from_intr at ffffffffbda0094e [exception RIP: unknown or invalid address] RIP: 000000000000001f RSP: 0000000000000000 RFLAGS: fff3b8c2091ebb3f RAX: ffffbba5a0000200 RBX: 0000be8cdfa8f9fa RCX: 0000000000000018 RDX: 0000000000000101 RSI: 000000000000015d RDI: 0000000000000193 RBP: 0000000000000083 R8: ffffffffbe403e38 R9: 0000000000000002 R10: 0000000000000000 R11: ffffffffbe56b820 R12: ffff891ee001cf00 R13: ffffffffbd11c0a4 R14: ffffffffbe403d60 R15: 0000000000000001 ORIG_RAX: ffff891ee0022ac0 CS: 0000 SS: ffffffffffffffb9 bt: WARNING: possibly bogus exception frame #21 [ffffffffbe403dd8] cpuidle_enter_state at ffffffffbd67c6fd #22 [ffffffffbe403e40] cpuidle_enter at ffffffffbd67c907 #23 [ffffffffbe403e50] call_cpuidle at ffffffffbd0d98f3 #24 [ffffffffbe403e60] do_idle at ffffffffbd0d9b42 #25 [ffffffffbe403e98] cpu_startup_entry at ffffffffbd0d9da3 #26 [ffffffffbe403ec0] rest_init at ffffffffbd81d4aa #27 [ffffffffbe403ed0] start_kernel at ffffffffbe67d2ca #28 [ffffffffbe403f28] x86_64_start_reservations at ffffffffbe67c675 #29 [ffffffffbe403f38] x86_64_start_kernel at ffffffffbe67c6eb #30 [ffffffffbe403f50] secondary_startup_64 at ffffffffbd0000d5 Fixes: 040036b ("scsi: qla2xxx: Delay loop id allocation at login") Cc: <stable@vger.kernel.org> # v4.17+ Signed-off-by: Chuck Anderson <chuck.anderson@oracle.com> Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

idryomov · 2018-10-12T12:56:04Z

http://tracker.ceph.com/issues/25150#note-4

Increase kasan instrumented kernel stack size from 32k to 64k. Other architectures seems to get away with just doubling kernel stack size under kasan, but on s390 this appears to be not enough due to bigger frame size. The particular pain point is kasan inlined checks (CONFIG_KASAN_INLINE vs CONFIG_KASAN_OUTLINE). With inlined checks one particular case hitting stack overflow is fs sync on xfs filesystem: #0 [9a0681e8] 704 bytes check_usage at 34b1fc #1 [9a0684a8] 432 bytes check_usage at 34c710 #2 [9a068658] 1048 bytes validate_chain at 35044a #3 [9a068a70] 312 bytes __lock_acquire at 3559fe #4 [9a068ba8] 440 bytes lock_acquire at 3576ee #5 [9a068d60] 104 bytes _raw_spin_lock at 21b44e0 #6 [9a068dc8] 1992 bytes enqueue_entity at 2dbf72 #7 [9a069590] 1496 bytes enqueue_task_fair at 2df5f0 #8 [9a069b68] 64 bytes ttwu_do_activate at 28f438 #9 [9a069ba8] 552 bytes try_to_wake_up at 298c4c #10 [9a069dd0] 168 bytes wake_up_worker at 23f97c #11 [9a069e78] 200 bytes insert_work at 23fc2e #12 [9a069f40] 648 bytes __queue_work at 2487c0 #13 [9a06a1c8] 200 bytes __queue_delayed_work at 24db28 #14 [9a06a290] 248 bytes mod_delayed_work_on at 24de84 #15 [9a06a388] 24 bytes kblockd_mod_delayed_work_on at 153e2a0 #16 [9a06a3a0] 288 bytes __blk_mq_delay_run_hw_queue at 158168c #17 [9a06a4c0] 192 bytes blk_mq_run_hw_queue at 1581a3c #18 [9a06a580] 184 bytes blk_mq_sched_insert_requests at 15a2192 #19 [9a06a638] 1024 bytes blk_mq_flush_plug_list at 1590f3a #20 [9a06aa38] 704 bytes blk_flush_plug_list at 1555028 #21 [9a06acf8] 320 bytes schedule at 219e476 #22 [9a06ae38] 760 bytes schedule_timeout at 21b0aac #23 [9a06b130] 408 bytes wait_for_common at 21a1706 #24 [9a06b2c8] 360 bytes xfs_buf_iowait at fa1540 #25 [9a06b430] 256 bytes __xfs_buf_submit at fadae6 #26 [9a06b530] 264 bytes xfs_buf_read_map at fae3f6 #27 [9a06b638] 656 bytes xfs_trans_read_buf_map at 10ac9a8 #28 [9a06b8c8] 304 bytes xfs_btree_kill_root at e72426 #29 [9a06b9f8] 288 bytes xfs_btree_lookup_get_block at e7bc5e #30 [9a06bb18] 624 bytes xfs_btree_lookup at e7e1a6 #31 [9a06bd88] 2664 bytes xfs_alloc_ag_vextent_near at dfa070 #32 [9a06c7f0] 144 bytes xfs_alloc_ag_vextent at dff3ca #33 [9a06c880] 1128 bytes xfs_alloc_vextent at e05fce #34 [9a06cce8] 584 bytes xfs_bmap_btalloc at e58342 #35 [9a06cf30] 1336 bytes xfs_bmapi_write at e618de #36 [9a06d468] 776 bytes xfs_iomap_write_allocate at ff678e #37 [9a06d770] 720 bytes xfs_map_blocks at f82af8 #38 [9a06da40] 928 bytes xfs_writepage_map at f83cd6 #39 [9a06dde0] 320 bytes xfs_do_writepage at f85872 #40 [9a06df20] 1320 bytes write_cache_pages at 73dfe8 #41 [9a06e448] 208 bytes xfs_vm_writepages at f7f892 #42 [9a06e518] 88 bytes do_writepages at 73fe6a #43 [9a06e570] 872 bytes __writeback_single_inode at a20cb6 #44 [9a06e8d8] 664 bytes writeback_sb_inodes at a23be2 #45 [9a06eb70] 296 bytes __writeback_inodes_wb at a242e0 #46 [9a06ec98] 928 bytes wb_writeback at a2500e #47 [9a06f038] 848 bytes wb_do_writeback at a260ae #48 [9a06f388] 536 bytes wb_workfn at a28228 #49 [9a06f5a0] 1088 bytes process_one_work at 24a234 #50 [9a06f9e0] 1120 bytes worker_thread at 24ba26 #51 [9a06fe40] 104 bytes kthread at 26545a #52 [9a06fea8] kernel_thread_starter at 21b6b62 To be able to increase the stack size to 64k reuse LLILL instruction in __switch_to function to load 64k - STACK_FRAME_OVERHEAD - __PT_SIZE (65192) value as unsigned. Reported-by: Benjamin Block <bblock@linux.ibm.com> Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

When IDLETIMER rule is added, sysfs file is created under /sys/class/xt_idletimer/timers/ But some label name shouldn't be used. ".", "..", "power", "uevent", "subsystem", etc... So that sysfs filename checking routine is needed. test commands: %iptables -I INPUT -j IDLETIMER --timeout 1 --label "power" splat looks like: [95765.423132] sysfs: cannot create duplicate filename '/devices/virtual/xt_idletimer/timers/power' [95765.433418] CPU: 0 PID: 8446 Comm: iptables Not tainted 4.19.0-rc6+ #20 [95765.449755] Call Trace: [95765.449755] dump_stack+0xc9/0x16b [95765.449755] ? show_regs_print_info+0x5/0x5 [95765.449755] sysfs_warn_dup+0x74/0x90 [95765.449755] sysfs_add_file_mode_ns+0x352/0x500 [95765.449755] sysfs_create_file_ns+0x179/0x270 [95765.449755] ? sysfs_add_file_mode_ns+0x500/0x500 [95765.449755] ? idletimer_tg_checkentry+0x3e5/0xb1b [xt_IDLETIMER] [95765.449755] ? rcu_read_lock_sched_held+0x114/0x130 [95765.449755] ? __kmalloc_track_caller+0x211/0x2b0 [95765.449755] ? memcpy+0x34/0x50 [95765.449755] idletimer_tg_checkentry+0x4e2/0xb1b [xt_IDLETIMER] [ ... ] Fixes: 0902b46 ("netfilter: xtables: idletimer target implementation") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Currently on driver bringup with KASAN enabled, meson triggers an OOB memory access as shown below: [ 117.904528] ================================================================== [ 117.904560] BUG: KASAN: global-out-of-bounds in meson_viu_set_osd_lut+0x7a0/0x890 [ 117.904588] Read of size 4 at addr ffff20000a63ce24 by task systemd-udevd/498 [ 117.904601] [ 118.083372] CPU: 4 PID: 498 Comm: systemd-udevd Not tainted 4.20.0-rc3Lyude-Test+ #20 [ 118.091143] Hardware name: amlogic khadas-vim2/khadas-vim2, BIOS 2018.07-rc2-armbian 09/11/2018 [ 118.099768] Call trace: [ 118.102181] dump_backtrace+0x0/0x3e8 [ 118.105796] show_stack+0x14/0x20 [ 118.109083] dump_stack+0x130/0x1c4 [ 118.112539] print_address_description+0x60/0x25c [ 118.117214] kasan_report+0x1b4/0x368 [ 118.120851] __asan_report_load4_noabort+0x18/0x20 [ 118.125566] meson_viu_set_osd_lut+0x7a0/0x890 [ 118.129953] meson_viu_init+0x10c/0x290 [ 118.133741] meson_drv_bind_master+0x474/0x748 [ 118.138141] meson_drv_bind+0x10/0x18 [ 118.141760] try_to_bring_up_master+0x3d8/0x768 [ 118.146249] component_add+0x214/0x570 [ 118.149978] meson_dw_hdmi_probe+0x18/0x20 [meson_dw_hdmi] [ 118.155404] platform_drv_probe+0x98/0x138 [ 118.159455] really_probe+0x2a0/0xa70 [ 118.163070] driver_probe_device+0x1b4/0x2d8 [ 118.167299] __driver_attach+0x200/0x280 [ 118.171189] bus_for_each_dev+0x10c/0x1a8 [ 118.175144] driver_attach+0x38/0x50 [ 118.178681] bus_add_driver+0x330/0x608 [ 118.182471] driver_register+0x140/0x388 [ 118.186361] __platform_driver_register+0xc8/0x108 [ 118.191117] meson_dw_hdmi_platform_driver_init+0x1c/0x1000 [meson_dw_hdmi] [ 118.198022] do_one_initcall+0x12c/0x3bc [ 118.201883] do_init_module+0x1fc/0x638 [ 118.205673] load_module+0x4b4c/0x6808 [ 118.209387] __se_sys_init_module+0x2e8/0x3c0 [ 118.213699] __arm64_sys_init_module+0x68/0x98 [ 118.218100] el0_svc_common+0x104/0x210 [ 118.221893] el0_svc_handler+0x48/0xb8 [ 118.225594] el0_svc+0x8/0xc [ 118.228429] [ 118.229887] The buggy address belongs to the variable: [ 118.235007] eotf_33_linear_mapping+0x84/0xc0 [ 118.239301] [ 118.240752] Memory state around the buggy address: [ 118.245522] ffff20000a63cd00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 118.252695] ffff20000a63cd80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 118.259850] >ffff20000a63ce00: 00 00 00 00 04 fa fa fa fa fa fa fa 00 00 00 00 [ 118.267000] ^ [ 118.271222] ffff20000a63ce80: 00 fa fa fa fa fa fa fa 00 00 00 00 00 00 00 00 [ 118.278393] ffff20000a63cf00: 00 00 00 00 00 00 00 00 00 00 00 00 04 fa fa fa [ 118.285542] ================================================================== [ 118.292699] Disabling lock debugging due to kernel taint It seems that when looping through the OSD EOTF LUT maps, we use the same max iterator for OETF: 20. This is wrong though, since 20*2 is 40, which means that we'll stop out of bounds on the EOTF maps. But, this whole thing is already confusing enough to read through as-is, so let's just replace all of the hardcoded sizes with OSD_(OETF/EOTF)_LUT_SIZE / 2. Signed-off-by: Lyude Paul <lyude@redhat.com> Fixes: bbbe775 ("drm: Add support for Amlogic Meson Graphic Controller") Cc: Neil Armstrong <narmstrong@baylibre.com> Cc: Maxime Ripard <maxime.ripard@bootlin.com> Cc: Carlo Caione <carlo@caione.org> Cc: Kevin Hilman <khilman@baylibre.com> Cc: dri-devel@lists.freedesktop.org Cc: linux-amlogic@lists.infradead.org Cc: linux-arm-kernel@lists.infradead.org Cc: <stable@vger.kernel.org> # v4.10+ Acked-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Link: https://patchwork.freedesktop.org/patch/msgid/20181125012117.31915-1-lyude@redhat.com Signed-off-by: Sean Paul <seanpaul@chromium.org>

…r-free issue The evlist should be destroyed before the perf session. Detected with gcc's ASan: ================================================================= ==27350==ERROR: AddressSanitizer: heap-use-after-free on address 0x62b000002e38 at pc 0x5611da276999 bp 0x7ffce8f1d1a0 sp 0x7ffce8f1d190 WRITE of size 8 at 0x62b000002e38 thread T0 #0 0x5611da276998 in __list_del /home/work/linux/tools/include/linux/list.h:89 #1 0x5611da276d4a in __list_del_entry /home/work/linux/tools/include/linux/list.h:102 #2 0x5611da276e77 in list_del_init /home/work/linux/tools/include/linux/list.h:145 #3 0x5611da2781cd in thread__put util/thread.c:130 #4 0x5611da2cc0a8 in __thread__zput util/thread.h:68 #5 0x5611da2d2dcb in hist_entry__delete util/hist.c:1148 #6 0x5611da2cdf91 in hists__delete_entry util/hist.c:337 #7 0x5611da2ce19e in hists__delete_entries util/hist.c:365 #8 0x5611da2db2ab in hists__delete_all_entries util/hist.c:2639 #9 0x5611da2db325 in hists_evsel__exit util/hist.c:2651 #10 0x5611da1c5352 in perf_evsel__exit util/evsel.c:1304 #11 0x5611da1c5390 in perf_evsel__delete util/evsel.c:1309 #12 0x5611da1b35f0 in perf_evlist__purge util/evlist.c:124 #13 0x5611da1b38e2 in perf_evlist__delete util/evlist.c:148 #14 0x5611da069781 in cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1645 #15 0x5611da17d038 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302 #16 0x5611da17d577 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354 #17 0x5611da17d97b in run_argv /home/changbin/work/linux/tools/perf/perf.c:398 #18 0x5611da17e0e9 in main /home/changbin/work/linux/tools/perf/perf.c:520 #19 0x7fdcc970f09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a) #20 0x5611d9ff35c9 in _start (/home/work/linux/tools/perf/perf+0x3e95c9) 0x62b000002e38 is located 11320 bytes inside of 27448-byte region [0x62b000000200,0x62b000006d38) freed by thread T0 here: #0 0x7fdccb04ab70 in free (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xedb70) #1 0x5611da260df4 in perf_session__delete util/session.c:201 #2 0x5611da063de5 in __cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1300 #3 0x5611da06973c in cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1642 #4 0x5611da17d038 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302 #5 0x5611da17d577 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354 #6 0x5611da17d97b in run_argv /home/changbin/work/linux/tools/perf/perf.c:398 #7 0x5611da17e0e9 in main /home/changbin/work/linux/tools/perf/perf.c:520 #8 0x7fdcc970f09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a) previously allocated by thread T0 here: #0 0x7fdccb04b138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138) #1 0x5611da26010c in zalloc util/util.h:23 #2 0x5611da260824 in perf_session__new util/session.c:118 #3 0x5611da0633a6 in __cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1192 #4 0x5611da06973c in cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1642 #5 0x5611da17d038 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302 #6 0x5611da17d577 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354 #7 0x5611da17d97b in run_argv /home/changbin/work/linux/tools/perf/perf.c:398 #8 0x5611da17e0e9 in main /home/changbin/work/linux/tools/perf/perf.c:520 #9 0x7fdcc970f09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a) SUMMARY: AddressSanitizer: heap-use-after-free /home/work/linux/tools/include/linux/list.h:89 in __list_del Shadow bytes around the buggy address: 0x0c567fff8570: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff8580: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff8590: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff85a0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff85b0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd =>0x0c567fff85c0: fd fd fd fd fd fd fd[fd]fd fd fd fd fd fd fd fd 0x0c567fff85d0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff85e0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff85f0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff8600: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd 0x0c567fff8610: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init order: f6 Poisoned by user: f7 Container overflow: fc Array cookie: ac Intra object redzone: bb ASan internal: fe Left alloca redzone: ca Right alloca redzone: cb ==27350==ABORTING Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20190316080556.3075-8-changbin.du@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Current snapshot implementation swaps two ring_buffers even though their sizes are different from each other, that can cause an inconsistency between the contents of buffer_size_kb file and the current buffer size. For example: # cat buffer_size_kb 7 (expanded: 1408) # echo 1 > events/enable # grep bytes per_cpu/cpu0/stats bytes: 1441020 # echo 1 > snapshot // current:1408, spare:1408 # echo 123 > buffer_size_kb // current:123, spare:1408 # echo 1 > snapshot // current:1408, spare:123 # grep bytes per_cpu/cpu0/stats bytes: 1443700 # cat buffer_size_kb 123 // != current:1408 And also, a similar per-cpu case hits the following WARNING: Reproducer: # echo 1 > per_cpu/cpu0/snapshot # echo 123 > buffer_size_kb # echo 1 > per_cpu/cpu0/snapshot WARNING: WARNING: CPU: 0 PID: 1946 at kernel/trace/trace.c:1607 update_max_tr_single.part.0+0x2b8/0x380 Modules linked in: CPU: 0 PID: 1946 Comm: bash Not tainted 5.2.0-rc6 #20 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-2.fc30 04/01/2014 RIP: 0010:update_max_tr_single.part.0+0x2b8/0x380 Code: ff e8 dc da f9 ff 0f 0b e9 88 fe ff ff e8 d0 da f9 ff 44 89 ee bf f5 ff ff ff e8 33 dc f9 ff 41 83 fd f5 74 96 e8 b8 da f9 ff <0f> 0b eb 8d e8 af da f9 ff 0f 0b e9 bf fd ff ff e8 a3 da f9 ff 48 RSP: 0018:ffff888063e4fca0 EFLAGS: 00010093 RAX: ffff888066214380 RBX: ffffffff99850fe0 RCX: ffffffff964298a8 RDX: 0000000000000000 RSI: 00000000fffffff5 RDI: 0000000000000005 RBP: 1ffff1100c7c9f96 R08: ffff888066214380 R09: ffffed100c7c9f9b R10: ffffed100c7c9f9a R11: 0000000000000003 R12: 0000000000000000 R13: 00000000ffffffea R14: ffff888066214380 R15: ffffffff99851060 FS: 00007f9f8173c700(0000) GS:ffff88806d000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000714dc0 CR3: 0000000066fa6000 CR4: 00000000000006f0 Call Trace: ? trace_array_printk_buf+0x140/0x140 ? __mutex_lock_slowpath+0x10/0x10 tracing_snapshot_write+0x4c8/0x7f0 ? trace_printk_init_buffers+0x60/0x60 ? selinux_file_permission+0x3b/0x540 ? tracer_preempt_off+0x38/0x506 ? trace_printk_init_buffers+0x60/0x60 __vfs_write+0x81/0x100 vfs_write+0x1e1/0x560 ksys_write+0x126/0x250 ? __ia32_sys_read+0xb0/0xb0 ? do_syscall_64+0x1f/0x390 do_syscall_64+0xc1/0x390 entry_SYSCALL_64_after_hwframe+0x49/0xbe This patch adds resize_buffer_duplicate_size() to check if there is a difference between current/spare buffer sizes and resize a spare buffer if necessary. Link: http://lkml.kernel.org/r/20190625012910.13109-1-devel@etsukata.com Cc: stable@vger.kernel.org Fixes: ad909e2 ("tracing: Add internal tracing_snapshot() functions") Signed-off-by: Eiichi Tsukata <devel@etsukata.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

Make debug exceptions visible from RCU so that synchronize_rcu() correctly track the debug exception handler. This also introduces sanity checks for user-mode exceptions as same as x86's ist_enter()/ist_exit(). The debug exception can interrupt in idle task. For example, it warns if we put a kprobe on a function called from idle task as below. The warning message showed that the rcu_read_lock() caused this problem. But actually, this means the RCU is lost the context which is already in NMI/IRQ. /sys/kernel/debug/tracing # echo p default_idle_call >> kprobe_events /sys/kernel/debug/tracing # echo 1 > events/kprobes/enable /sys/kernel/debug/tracing # [ 135.122237] [ 135.125035] ============================= [ 135.125310] WARNING: suspicious RCU usage [ 135.125581] 5.2.0-08445-g9187c508bdc7 #20 Not tainted [ 135.125904] ----------------------------- [ 135.126205] include/linux/rcupdate.h:594 rcu_read_lock() used illegally while idle! [ 135.126839] [ 135.126839] other info that might help us debug this: [ 135.126839] [ 135.127410] [ 135.127410] RCU used illegally from idle CPU! [ 135.127410] rcu_scheduler_active = 2, debug_locks = 1 [ 135.128114] RCU used illegally from extended quiescent state! [ 135.128555] 1 lock held by swapper/0/0: [ 135.128944] #0: (____ptrval____) (rcu_read_lock){....}, at: call_break_hook+0x0/0x178 [ 135.130499] [ 135.130499] stack backtrace: [ 135.131192] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.2.0-08445-g9187c508bdc7 #20 [ 135.131841] Hardware name: linux,dummy-virt (DT) [ 135.132224] Call trace: [ 135.132491] dump_backtrace+0x0/0x140 [ 135.132806] show_stack+0x24/0x30 [ 135.133133] dump_stack+0xc4/0x10c [ 135.133726] lockdep_rcu_suspicious+0xf8/0x108 [ 135.134171] call_break_hook+0x170/0x178 [ 135.134486] brk_handler+0x28/0x68 [ 135.134792] do_debug_exception+0x90/0x150 [ 135.135051] el1_dbg+0x18/0x8c [ 135.135260] default_idle_call+0x0/0x44 [ 135.135516] cpu_startup_entry+0x2c/0x30 [ 135.135815] rest_init+0x1b0/0x280 [ 135.136044] arch_call_rest_init+0x14/0x1c [ 135.136305] start_kernel+0x4d4/0x500 [ 135.136597] So make debug exception visible to RCU can fix this warning. Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> Acked-by: Paul E. McKenney <paulmck@linux.ibm.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Will Deacon <will@kernel.org>

A deadlock with this stacktrace was observed. The loop thread does a GFP_KERNEL allocation, it calls into dm-bufio shrinker and the shrinker depends on I/O completion in the dm-bufio subsystem. In order to fix the deadlock (and other similar ones), we set the flag PF_MEMALLOC_NOIO at loop thread entry. PID: 474 TASK: ffff8813e11f4600 CPU: 10 COMMAND: "kswapd0" #0 [ffff8813dedfb938] __schedule at ffffffff8173f405 #1 [ffff8813dedfb990] schedule at ffffffff8173fa27 #2 [ffff8813dedfb9b0] schedule_timeout at ffffffff81742fec #3 [ffff8813dedfba60] io_schedule_timeout at ffffffff8173f186 #4 [ffff8813dedfbaa0] bit_wait_io at ffffffff8174034f #5 [ffff8813dedfbac0] __wait_on_bit at ffffffff8173fec8 #6 [ffff8813dedfbb10] out_of_line_wait_on_bit at ffffffff8173ff81 #7 [ffff8813dedfbb90] __make_buffer_clean at ffffffffa038736f [dm_bufio] #8 [ffff8813dedfbbb0] __try_evict_buffer at ffffffffa0387bb8 [dm_bufio] #9 [ffff8813dedfbbd0] dm_bufio_shrink_scan at ffffffffa0387cc3 [dm_bufio] #10 [ffff8813dedfbc40] shrink_slab at ffffffff811a87ce #11 [ffff8813dedfbd30] shrink_zone at ffffffff811ad778 #12 [ffff8813dedfbdc0] kswapd at ffffffff811ae92f #13 [ffff8813dedfbec0] kthread at ffffffff810a8428 #14 [ffff8813dedfbf50] ret_from_fork at ffffffff81745242 PID: 14127 TASK: ffff881455749c00 CPU: 11 COMMAND: "loop1" #0 [ffff88272f5af228] __schedule at ffffffff8173f405 #1 [ffff88272f5af280] schedule at ffffffff8173fa27 #2 [ffff88272f5af2a0] schedule_preempt_disabled at ffffffff8173fd5e #3 [ffff88272f5af2b0] __mutex_lock_slowpath at ffffffff81741fb5 #4 [ffff88272f5af330] mutex_lock at ffffffff81742133 #5 [ffff88272f5af350] dm_bufio_shrink_count at ffffffffa03865f9 [dm_bufio] #6 [ffff88272f5af380] shrink_slab at ffffffff811a86bd #7 [ffff88272f5af470] shrink_zone at ffffffff811ad778 #8 [ffff88272f5af500] do_try_to_free_pages at ffffffff811adb34 #9 [ffff88272f5af590] try_to_free_pages at ffffffff811adef8 #10 [ffff88272f5af610] __alloc_pages_nodemask at ffffffff811a09c3 #11 [ffff88272f5af710] alloc_pages_current at ffffffff811e8b71 #12 [ffff88272f5af760] new_slab at ffffffff811f4523 #13 [ffff88272f5af7b0] __slab_alloc at ffffffff8173a1b5 #14 [ffff88272f5af880] kmem_cache_alloc at ffffffff811f484b #15 [ffff88272f5af8d0] do_blockdev_direct_IO at ffffffff812535b3 #16 [ffff88272f5afb00] __blockdev_direct_IO at ffffffff81255dc3 #17 [ffff88272f5afb30] xfs_vm_direct_IO at ffffffffa01fe3fc [xfs] #18 [ffff88272f5afb90] generic_file_read_iter at ffffffff81198994 #19 [ffff88272f5afc50] __dta_xfs_file_read_iter_2398 at ffffffffa020c970 [xfs] #20 [ffff88272f5afcc0] lo_rw_aio at ffffffffa0377042 [loop] #21 [ffff88272f5afd70] loop_queue_work at ffffffffa0377c3b [loop] #22 [ffff88272f5afe60] kthread_worker_fn at ffffffff810a8a0c #23 [ffff88272f5afec0] kthread at ffffffff810a8428 #24 [ffff88272f5aff50] ret_from_fork at ffffffff81745242 Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>

When experimenting with bpf_send_signal() helper in our production environment (5.2 based), we experienced a deadlock in NMI mode: #5 [ffffc9002219f770] queued_spin_lock_slowpath at ffffffff8110be24 #6 [ffffc9002219f770] _raw_spin_lock_irqsave at ffffffff81a43012 #7 [ffffc9002219f780] try_to_wake_up at ffffffff810e7ecd #8 [ffffc9002219f7e0] signal_wake_up_state at ffffffff810c7b55 #9 [ffffc9002219f7f0] __send_signal at ffffffff810c8602 #10 [ffffc9002219f830] do_send_sig_info at ffffffff810ca31a #11 [ffffc9002219f868] bpf_send_signal at ffffffff8119d227 #12 [ffffc9002219f988] bpf_overflow_handler at ffffffff811d4140 #13 [ffffc9002219f9e0] __perf_event_overflow at ffffffff811d68cf #14 [ffffc9002219fa10] perf_swevent_overflow at ffffffff811d6a09 #15 [ffffc9002219fa38] ___perf_sw_event at ffffffff811e0f47 #16 [ffffc9002219fc30] __schedule at ffffffff81a3e04d #17 [ffffc9002219fc90] schedule at ffffffff81a3e219 #18 [ffffc9002219fca0] futex_wait_queue_me at ffffffff8113d1b9 #19 [ffffc9002219fcd8] futex_wait at ffffffff8113e529 #20 [ffffc9002219fdf0] do_futex at ffffffff8113ffbc #21 [ffffc9002219fec0] __x64_sys_futex at ffffffff81140d1c #22 [ffffc9002219ff38] do_syscall_64 at ffffffff81002602 #23 [ffffc9002219ff50] entry_SYSCALL_64_after_hwframe at ffffffff81c00068 The above call stack is actually very similar to an issue reported by Commit eac9153 ("bpf/stackmap: Fix deadlock with rq_lock in bpf_get_stack()") by Song Liu. The only difference is bpf_send_signal() helper instead of bpf_get_stack() helper. The above deadlock is triggered with a perf_sw_event. Similar to Commit eac9153, the below almost identical reproducer used tracepoint point sched/sched_switch so the issue can be easily caught. /* stress_test.c */ #include <stdio.h> #include <stdlib.h> #include <sys/mman.h> #include <pthread.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #define THREAD_COUNT 1000 char *filename; void *worker(void *p) { void *ptr; int fd; char *pptr; fd = open(filename, O_RDONLY); if (fd < 0) return NULL; while (1) { struct timespec ts = {0, 1000 + rand() % 2000}; ptr = mmap(NULL, 4096 * 64, PROT_READ, MAP_PRIVATE, fd, 0); usleep(1); if (ptr == MAP_FAILED) { printf("failed to mmap\n"); break; } munmap(ptr, 4096 * 64); usleep(1); pptr = malloc(1); usleep(1); pptr[0] = 1; usleep(1); free(pptr); usleep(1); nanosleep(&ts, NULL); } close(fd); return NULL; } int main(int argc, char *argv[]) { void *ptr; int i; pthread_t threads[THREAD_COUNT]; if (argc < 2) return 0; filename = argv[1]; for (i = 0; i < THREAD_COUNT; i++) { if (pthread_create(threads + i, NULL, worker, NULL)) { fprintf(stderr, "Error creating thread\n"); return 0; } } for (i = 0; i < THREAD_COUNT; i++) pthread_join(threads[i], NULL); return 0; } and the following command: 1. run `stress_test /bin/ls` in one windown 2. hack bcc trace.py with the following change: --- a/tools/trace.py +++ b/tools/trace.py @@ -513,6 +513,7 @@ BPF_PERF_OUTPUT(%s); __data.tgid = __tgid; __data.pid = __pid; bpf_get_current_comm(&__data.comm, sizeof(__data.comm)); + bpf_send_signal(10); %s %s %s.perf_submit(%s, &__data, sizeof(__data)); 3. in a different window run ./trace.py -p $(pidof stress_test) t:sched:sched_switch The deadlock can be reproduced in our production system. Similar to Song's fix, the fix is to delay sending signal if irqs is disabled to avoid deadlocks involving with rq_lock. With this change, my above stress-test in our production system won't cause deadlock any more. I also implemented a scale-down version of reproducer in the selftest (a subsequent commit). With latest bpf-next, it complains for the following potential deadlock. [ 32.832450] -> #1 (&p->pi_lock){-.-.}: [ 32.833100] _raw_spin_lock_irqsave+0x44/0x80 [ 32.833696] task_rq_lock+0x2c/0xa0 [ 32.834182] task_sched_runtime+0x59/0xd0 [ 32.834721] thread_group_cputime+0x250/0x270 [ 32.835304] thread_group_cputime_adjusted+0x2e/0x70 [ 32.835959] do_task_stat+0x8a7/0xb80 [ 32.836461] proc_single_show+0x51/0xb0 ... [ 32.839512] -> #0 (&(&sighand->siglock)->rlock){....}: [ 32.840275] __lock_acquire+0x1358/0x1a20 [ 32.840826] lock_acquire+0xc7/0x1d0 [ 32.841309] _raw_spin_lock_irqsave+0x44/0x80 [ 32.841916] __lock_task_sighand+0x79/0x160 [ 32.842465] do_send_sig_info+0x35/0x90 [ 32.842977] bpf_send_signal+0xa/0x10 [ 32.843464] bpf_prog_bc13ed9e4d3163e3_send_signal_tp_sched+0x465/0x1000 [ 32.844301] trace_call_bpf+0x115/0x270 [ 32.844809] perf_trace_run_bpf_submit+0x4a/0xc0 [ 32.845411] perf_trace_sched_switch+0x10f/0x180 [ 32.846014] __schedule+0x45d/0x880 [ 32.846483] schedule+0x5f/0xd0 ... [ 32.853148] Chain exists of: [ 32.853148] &(&sighand->siglock)->rlock --> &p->pi_lock --> &rq->lock [ 32.853148] [ 32.854451] Possible unsafe locking scenario: [ 32.854451] [ 32.855173] CPU0 CPU1 [ 32.855745] ---- ---- [ 32.856278] lock(&rq->lock); [ 32.856671] lock(&p->pi_lock); [ 32.857332] lock(&rq->lock); [ 32.857999] lock(&(&sighand->siglock)->rlock); Deadlock happens on CPU0 when it tries to acquire &sighand->siglock but it has been held by CPU1 and CPU1 tries to grab &rq->lock and cannot get it. This is not exactly the callstack in our production environment, but sympotom is similar and both locks are using spin_lock_irqsave() to acquire the lock, and both involves rq_lock. The fix to delay sending signal when irq is disabled also fixed this issue. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Cc: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20200304191104.2796501-1-yhs@fb.com

I compiled with AddressSanitizer and I had these memory leaks while I was using the tep_parse_format function: Direct leak of 28 byte(s) in 4 object(s) allocated from: #0 0x7fb07db49ffe in __interceptor_realloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10dffe) #1 0x7fb07a724228 in extend_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:985 #2 0x7fb07a724c21 in __read_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1140 #3 0x7fb07a724f78 in read_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1206 #4 0x7fb07a725191 in __read_expect_type /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1291 #5 0x7fb07a7251df in read_expect_type /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1299 #6 0x7fb07a72e6c8 in process_dynamic_array_len /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:2849 #7 0x7fb07a7304b8 in process_function /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3161 #8 0x7fb07a730900 in process_arg_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3207 #9 0x7fb07a727c0b in process_arg /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1786 #10 0x7fb07a731080 in event_read_print_args /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3285 #11 0x7fb07a731722 in event_read_print /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3369 #12 0x7fb07a740054 in __tep_parse_format /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6335 #13 0x7fb07a74047a in __parse_event /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6389 #14 0x7fb07a740536 in tep_parse_format /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6431 #15 0x7fb07a785acf in parse_event ../../../src/fs-src/fs.c:251 #16 0x7fb07a785ccd in parse_systems ../../../src/fs-src/fs.c:284 #17 0x7fb07a786fb3 in read_metadata ../../../src/fs-src/fs.c:593 #18 0x7fb07a78760e in ftrace_fs_source_init ../../../src/fs-src/fs.c:727 #19 0x7fb07d90c19c in add_component_with_init_method_data ../../../../src/lib/graph/graph.c:1048 #20 0x7fb07d90c87b in add_source_component_with_initialize_method_data ../../../../src/lib/graph/graph.c:1127 #21 0x7fb07d90c92a in bt_graph_add_source_component ../../../../src/lib/graph/graph.c:1152 #22 0x55db11aa632e in cmd_run_ctx_create_components_from_config_components ../../../src/cli/babeltrace2.c:2252 #23 0x55db11aa6fda in cmd_run_ctx_create_components ../../../src/cli/babeltrace2.c:2347 #24 0x55db11aa780c in cmd_run ../../../src/cli/babeltrace2.c:2461 #25 0x55db11aa8a7d in main ../../../src/cli/babeltrace2.c:2673 #26 0x7fb07d5460b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2) The token variable in the process_dynamic_array_len function is allocated in the read_expect_type function, but is not freed before calling the read_token function. Free the token variable before calling read_token in order to plug the leak. Signed-off-by: Philippe Duplessis-Guindon <pduplessis@efficios.com> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Link: https://lore.kernel.org/linux-trace-devel/20200730150236.5392-1-pduplessis@efficios.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The test_generic_metric() missed to release entries in the pctx. Asan reported following leak (and more): Direct leak of 128 byte(s) in 1 object(s) allocated from: #0 0x7f4c9396980e in calloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10780e) #1 0x55f7e748cc14 in hashmap_grow (/home/namhyung/project/linux/tools/perf/perf+0x90cc14) #2 0x55f7e748d497 in hashmap__insert (/home/namhyung/project/linux/tools/perf/perf+0x90d497) #3 0x55f7e7341667 in hashmap__set /home/namhyung/project/linux/tools/perf/util/hashmap.h:111 #4 0x55f7e7341667 in expr__add_ref util/expr.c:120 #5 0x55f7e7292436 in prepare_metric util/stat-shadow.c:783 #6 0x55f7e729556d in test_generic_metric util/stat-shadow.c:858 #7 0x55f7e712390b in compute_single tests/parse-metric.c:128 #8 0x55f7e712390b in __compute_metric tests/parse-metric.c:180 #9 0x55f7e712446d in compute_metric tests/parse-metric.c:196 #10 0x55f7e712446d in test_dcache_l2 tests/parse-metric.c:295 #11 0x55f7e712446d in test__parse_metric tests/parse-metric.c:355 #12 0x55f7e70be09b in run_test tests/builtin-test.c:410 #13 0x55f7e70be09b in test_and_print tests/builtin-test.c:440 #14 0x55f7e70c101a in __cmd_test tests/builtin-test.c:661 #15 0x55f7e70c101a in cmd_test tests/builtin-test.c:807 #16 0x55f7e7126214 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312 #17 0x55f7e6fc41a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364 #18 0x55f7e6fc41a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408 #19 0x55f7e6fc41a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538 #20 0x7f4c93492cc9 in __libc_start_main ../csu/libc-start.c:308 Fixes: 6d432c4 ("perf tools: Add test_generic_metric function") Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20200915031819.386559-8-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

This fix is for a failure that occurred in the DWARF unwind perf test. Stack unwinders may probe memory when looking for frames. Memory sanitizer will poison and track uninitialized memory on the stack, and on the heap if the value is copied to the heap. This can lead to false memory sanitizer failures for the use of an uninitialized value. Avoid this problem by removing the poison on the copied stack. The full msan failure with track origins looks like: ==2168==WARNING: MemorySanitizer: use-of-uninitialized-value #0 0x559ceb10755b in handle_cfi elfutils/libdwfl/frame_unwind.c:648:8 #1 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4 #2 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7 #3 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10 #4 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17 #5 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17 #6 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14 #7 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10 #8 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8 #9 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8 #10 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #11 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #12 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #13 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #14 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #15 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #16 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #17 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #18 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #19 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #20 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #21 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #22 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #23 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was stored to memory at #0 0x559ceb106acf in __libdwfl_frame_reg_set elfutils/libdwfl/frame_unwind.c:77:22 #1 0x559ceb106acf in handle_cfi elfutils/libdwfl/frame_unwind.c:627:13 #2 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4 #3 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7 #4 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10 #5 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17 #6 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17 #7 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14 #8 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10 #9 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8 #10 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8 #11 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #12 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #13 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #14 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #15 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #16 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #17 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #18 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #19 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #20 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #21 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #22 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #23 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #24 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was stored to memory at #0 0x559ceb106a54 in handle_cfi elfutils/libdwfl/frame_unwind.c:613:9 #1 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4 #2 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7 #3 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10 #4 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17 #5 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17 #6 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14 #7 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10 #8 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8 #9 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8 #10 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #11 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #12 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #13 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #14 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #15 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #16 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #17 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #18 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #19 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #20 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #21 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #22 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #23 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was stored to memory at #0 0x559ceaff8800 in memory_read tools/perf/util/unwind-libdw.c:156:10 #1 0x559ceb10f053 in expr_eval elfutils/libdwfl/frame_unwind.c:501:13 #2 0x559ceb1060cc in handle_cfi elfutils/libdwfl/frame_unwind.c:603:18 #3 0x559ceb105448 in __libdwfl_frame_unwind elfutils/libdwfl/frame_unwind.c:741:4 #4 0x559ceb0ece90 in dwfl_thread_getframes elfutils/libdwfl/dwfl_frame.c:435:7 #5 0x559ceb0ec6b7 in get_one_thread_frames_cb elfutils/libdwfl/dwfl_frame.c:379:10 #6 0x559ceb0ec6b7 in get_one_thread_cb elfutils/libdwfl/dwfl_frame.c:308:17 #7 0x559ceb0ec6b7 in dwfl_getthreads elfutils/libdwfl/dwfl_frame.c:283:17 #8 0x559ceb0ec6b7 in getthread elfutils/libdwfl/dwfl_frame.c:354:14 #9 0x559ceb0ec6b7 in dwfl_getthread_frames elfutils/libdwfl/dwfl_frame.c:388:10 #10 0x559ceaff6ae6 in unwind__get_entries tools/perf/util/unwind-libdw.c:236:8 #11 0x559ceabc9dbc in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:111:8 #12 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #13 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #14 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #15 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #16 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #17 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #18 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #19 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #20 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #21 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #22 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #23 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #24 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #25 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was stored to memory at #0 0x559cea9027d9 in __msan_memcpy llvm/llvm-project/compiler-rt/lib/msan/msan_interceptors.cpp:1558:3 #1 0x559cea9d2185 in sample_ustack tools/perf/arch/x86/tests/dwarf-unwind.c:41:2 #2 0x559cea9d202c in test__arch_unwind_sample tools/perf/arch/x86/tests/dwarf-unwind.c:72:9 #3 0x559ceabc9cbd in test_dwarf_unwind__thread tools/perf/tests/dwarf-unwind.c:106:6 #4 0x559ceabca5cf in test_dwarf_unwind__compare tools/perf/tests/dwarf-unwind.c:138:26 #5 0x7f812a6865b0 in bsearch (libc.so.6+0x4e5b0) #6 0x559ceabca871 in test_dwarf_unwind__krava_3 tools/perf/tests/dwarf-unwind.c:162:2 #7 0x559ceabca926 in test_dwarf_unwind__krava_2 tools/perf/tests/dwarf-unwind.c:169:9 #8 0x559ceabca946 in test_dwarf_unwind__krava_1 tools/perf/tests/dwarf-unwind.c:174:9 #9 0x559ceabcae12 in test__dwarf_unwind tools/perf/tests/dwarf-unwind.c:211:8 #10 0x559ceabbc4ab in run_test tools/perf/tests/builtin-test.c:418:9 #11 0x559ceabbc4ab in test_and_print tools/perf/tests/builtin-test.c:448:9 #12 0x559ceabbac70 in __cmd_test tools/perf/tests/builtin-test.c:669:4 #13 0x559ceabbac70 in cmd_test tools/perf/tests/builtin-test.c:815:9 #14 0x559cea960e30 in run_builtin tools/perf/perf.c:313:11 #15 0x559cea95fbce in handle_internal_command tools/perf/perf.c:365:8 #16 0x559cea95fbce in run_argv tools/perf/perf.c:409:2 #17 0x559cea95fbce in main tools/perf/perf.c:539:3 Uninitialized value was created by an allocation of 'bf' in the stack frame of function 'perf_event__synthesize_mmap_events' #0 0x559ceafc5f60 in perf_event__synthesize_mmap_events tools/perf/util/synthetic-events.c:445 SUMMARY: MemorySanitizer: use-of-uninitialized-value elfutils/libdwfl/frame_unwind.c:648:8 in handle_cfi Signed-off-by: Ian Rogers <irogers@google.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: clang-built-linux@googlegroups.com Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sandeep Dasgupta <sdasgup@google.com> Cc: Stephane Eranian <eranian@google.com> Link: http://lore.kernel.org/lkml/20201113182053.754625-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

The evlist and the cpu/thread maps should be released together. Otherwise following error was reported by Asan. Note that this test still has memory leaks in DSOs so it still fails even after this change. I'll take a look at that too. # perf test -v 26 26: Object code reading : --- start --- test child forked, pid 154184 Looking at the vmlinux_path (8 entries long) symsrc__init: build id mismatch for vmlinux. symsrc__init: cannot get elf header. Using /proc/kcore for kernel data Using /proc/kallsyms for symbols Parsing event 'cycles' mmap size 528384B ... ================================================================= ==154184==ERROR: LeakSanitizer: detected memory leaks Direct leak of 439 byte(s) in 1 object(s) allocated from: #0 0x7fcb66e77037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154 #1 0x55ad9b7e821e in dso__new_id util/dso.c:1256 #2 0x55ad9b8cfd4a in __machine__addnew_vdso util/vdso.c:132 #3 0x55ad9b8cfd4a in machine__findnew_vdso util/vdso.c:347 #4 0x55ad9b845b7e in map__new util/map.c:176 #5 0x55ad9b8415a2 in machine__process_mmap2_event util/machine.c:1787 #6 0x55ad9b8fab16 in perf_tool__process_synth_event util/synthetic-events.c:64 #7 0x55ad9b8fab16 in perf_event__synthesize_mmap_events util/synthetic-events.c:499 #8 0x55ad9b8fbfdf in __event__synthesize_thread util/synthetic-events.c:741 #9 0x55ad9b8ff3e3 in perf_event__synthesize_thread_map util/synthetic-events.c:833 #10 0x55ad9b738585 in do_test_code_reading tests/code-reading.c:608 #11 0x55ad9b73b25d in test__code_reading tests/code-reading.c:722 #12 0x55ad9b6f28fb in run_test tests/builtin-test.c:428 #13 0x55ad9b6f28fb in test_and_print tests/builtin-test.c:458 #14 0x55ad9b6f4a53 in __cmd_test tests/builtin-test.c:679 #15 0x55ad9b6f4a53 in cmd_test tests/builtin-test.c:825 #16 0x55ad9b760cc4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 #17 0x55ad9b5eaa88 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 #18 0x55ad9b5eaa88 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 #19 0x55ad9b5eaa88 in main /home/namhyung/project/linux/tools/perf/perf.c:539 #20 0x7fcb669acd09 in __libc_start_main ../csu/libc-start.c:308 ... SUMMARY: AddressSanitizer: 471 byte(s) leaked in 2 allocation(s). test child finished with 1 ---- end ---- Object code reading: FAILED! Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: https://lore.kernel.org/r/20210301140409.184570-6-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

I got several memory leak reports from Asan with a simple command. It was because VDSO is not released due to the refcount. Like in __dsos_addnew_id(), it should put the refcount after adding to the list. $ perf record true [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.030 MB perf.data (10 samples) ] ================================================================= ==692599==ERROR: LeakSanitizer: detected memory leaks Direct leak of 439 byte(s) in 1 object(s) allocated from: #0 0x7fea52341037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154 #1 0x559bce4aa8ee in dso__new_id util/dso.c:1256 #2 0x559bce59245a in __machine__addnew_vdso util/vdso.c:132 #3 0x559bce59245a in machine__findnew_vdso util/vdso.c:347 #4 0x559bce50826c in map__new util/map.c:175 #5 0x559bce503c92 in machine__process_mmap2_event util/machine.c:1787 #6 0x559bce512f6b in machines__deliver_event util/session.c:1481 #7 0x559bce515107 in perf_session__deliver_event util/session.c:1551 #8 0x559bce51d4d2 in do_flush util/ordered-events.c:244 #9 0x559bce51d4d2 in __ordered_events__flush util/ordered-events.c:323 #10 0x559bce519bea in __perf_session__process_events util/session.c:2268 #11 0x559bce519bea in perf_session__process_events util/session.c:2297 #12 0x559bce2e7a52 in process_buildids /home/namhyung/project/linux/tools/perf/builtin-record.c:1017 #13 0x559bce2e7a52 in record__finish_output /home/namhyung/project/linux/tools/perf/builtin-record.c:1234 #14 0x559bce2ed4f6 in __cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2026 #15 0x559bce2ed4f6 in cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2858 #16 0x559bce422db4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 #17 0x559bce2acac8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 #18 0x559bce2acac8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 #19 0x559bce2acac8 in main /home/namhyung/project/linux/tools/perf/perf.c:539 #20 0x7fea51e76d09 in __libc_start_main ../csu/libc-start.c:308 Indirect leak of 32 byte(s) in 1 object(s) allocated from: #0 0x7fea52341037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154 #1 0x559bce520907 in nsinfo__copy util/namespaces.c:169 #2 0x559bce50821b in map__new util/map.c:168 #3 0x559bce503c92 in machine__process_mmap2_event util/machine.c:1787 #4 0x559bce512f6b in machines__deliver_event util/session.c:1481 #5 0x559bce515107 in perf_session__deliver_event util/session.c:1551 #6 0x559bce51d4d2 in do_flush util/ordered-events.c:244 #7 0x559bce51d4d2 in __ordered_events__flush util/ordered-events.c:323 #8 0x559bce519bea in __perf_session__process_events util/session.c:2268 #9 0x559bce519bea in perf_session__process_events util/session.c:2297 #10 0x559bce2e7a52 in process_buildids /home/namhyung/project/linux/tools/perf/builtin-record.c:1017 #11 0x559bce2e7a52 in record__finish_output /home/namhyung/project/linux/tools/perf/builtin-record.c:1234 #12 0x559bce2ed4f6 in __cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2026 #13 0x559bce2ed4f6 in cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2858 #14 0x559bce422db4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313 #15 0x559bce2acac8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365 #16 0x559bce2acac8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409 #17 0x559bce2acac8 in main /home/namhyung/project/linux/tools/perf/perf.c:539 #18 0x7fea51e76d09 in __libc_start_main ../csu/libc-start.c:308 SUMMARY: AddressSanitizer: 471 byte(s) leaked in 2 allocation(s). Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Jiri Olsa <jolsa@redhat.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lore.kernel.org/lkml/20210315045641.700430-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

When the kernel is built with CONFIG_KASAN_HW_TAGS and the CPU supports MTE, memory accesses are checked at 16-byte granularity, and out-of-bounds accesses can result in tag check faults. Our current implementation of strlen() makes unaligned 16-byte accesses (within a naturally aligned 4096-byte window), and can trigger tag check faults. This can be seen at boot time, e.g. | BUG: KASAN: invalid-access in __pi_strlen+0x14/0x150 | Read at addr f4ff0000c0028300 by task swapper/0/0 | Pointer tag: [f4], memory tag: [fe] | | CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.13.0-09550-g03c2813535a2-dirty #20 | Hardware name: linux,dummy-virt (DT) | Call trace: | dump_backtrace+0x0/0x1b0 | show_stack+0x1c/0x30 | dump_stack_lvl+0x68/0x84 | print_address_description+0x7c/0x2b4 | kasan_report+0x138/0x38c | __do_kernel_fault+0x190/0x1c4 | do_tag_check_fault+0x78/0x90 | do_mem_abort+0x44/0xb4 | el1_abort+0x40/0x60 | el1h_64_sync_handler+0xb0/0xd0 | el1h_64_sync+0x78/0x7c | __pi_strlen+0x14/0x150 | __register_sysctl_table+0x7c4/0x890 | register_leaf_sysctl_tables+0x1a4/0x210 | register_leaf_sysctl_tables+0xc8/0x210 | __register_sysctl_paths+0x22c/0x290 | register_sysctl_table+0x2c/0x40 | sysctl_init+0x20/0x30 | proc_sys_init+0x3c/0x48 | proc_root_init+0x80/0x9c | start_kernel+0x640/0x69c | __primary_switched+0xc0/0xc8 To fix this, we can reduce the (strlen-internal) MIN_PAGE_SIZE to 16 bytes when CONFIG_KASAN_HW_TAGS is selected. This will cause strlen() to align the base pointer downwards to a 16-byte boundary, and to discard the additional prefix bytes without counting them. All subsequent accesses will be 16-byte aligned 16-byte LDPs. While the comments say the body of the loop will access 32 bytes, this is performed as two 16-byte acceses, with the second made only if the first did not encounter a NUL byte, so the body of the loop will not over-read across a 16-byte boundary. No other string routines are affected. The other str*() routines will not make any access which straddles a 16-byte boundary, and the mem*() routines will only make acceses which straddle a 16-byte boundary when which is entirely within the bounds of the relevant base and size arguments. Fixes: 325a1de ("arm64: Import updated version of Cortex Strings' strlen") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Alexander Potapenko <glider@google.com Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Marco Elver <elver@google.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Will Deacon <will@kernel.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Link: https://lore.kernel.org/r/20210712090043.20847-1-mark.rutland@arm.com Signed-off-by: Will Deacon <will@kernel.org>

arm32 uses software to simulate the instruction replaced by kprobe. some instructions may be simulated by constructing assembly functions. therefore, before executing instruction simulation, it is necessary to construct assembly function execution environment in C language through binding registers. after kasan is enabled, the register binding relationship will be destroyed, resulting in instruction simulation errors and causing kernel panic. the kprobe emulate instruction function is distributed in three files: actions-common.c actions-arm.c actions-thumb.c, so disable KASAN when compiling these files. for example, use kprobe insert on cap_capable+20 after kasan enabled, the cap_capable assembly code is as follows: <cap_capable>: e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr} e1a05000 mov r5, r0 e280006c add r0, r0, #108 ; 0x6c e1a04001 mov r4, r1 e1a06002 mov r6, r2 e59fa090 ldr sl, [pc, #144] ; ebfc7bf8 bl c03aa4b4 <__asan_load4> e595706c ldr r7, [r5, #108] ; 0x6c e2859014 add r9, r5, #20 ...... The emulate_ldr assembly code after enabling kasan is as follows: c06f1384 <emulate_ldr>: e92d47f0 push {r4, r5, r6, r7, r8, r9, sl, lr} e282803c add r8, r2, #60 ; 0x3c e1a05000 mov r5, r0 e7e37855 ubfx r7, r5, #16, #4 e1a00008 mov r0, r8 e1a09001 mov r9, r1 e1a04002 mov r4, r2 ebf35462 bl c03c6530 <__asan_load4> e357000f cmp r7, #15 e7e36655 ubfx r6, r5, #12, #4 e205a00f and sl, r5, #15 0a000001 beq c06f13bc <emulate_ldr+0x38> e0840107 add r0, r4, r7, lsl #2 ebf3545c bl c03c6530 <__asan_load4> e084010a add r0, r4, sl, lsl #2 ebf3545a bl c03c6530 <__asan_load4> e2890010 add r0, r9, #16 ebf35458 bl c03c6530 <__asan_load4> e5990010 ldr r0, [r9, #16] e12fff30 blx r0 e356000f cm r6, #15 1a000014 bne c06f1430 <emulate_ldr+0xac> e1a06000 mov r6, r0 e2840040 add r0, r4, #64 ; 0x40 ...... when running in emulate_ldr to simulate the ldr instruction, panic occurred, and the log is as follows: Unable to handle kernel NULL pointer dereference at virtual address 00000090 pgd = ecb46400 [00000090] *pgd=2e0fa003, *pmd=00000000 Internal error: Oops: 206 [#1] SMP ARM PC is at cap_capable+0x14/0xb0 LR is at emulate_ldr+0x50/0xc0 psr: 600d0293 sp : ecd63af8 ip : 00000004 fp : c0a7c30c r10: 00000000 r9 : c30897f4 r8 : ecd63cd4 r7 : 0000000f r6 : 0000000a r5 : e59fa090 r4 : ecd63c98 r3 : c06ae294 r2 : 00000000 r1 : b7611300 r0 : bf4ec008 Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user Control: 32c5387d Table: 2d546400 DAC: 55555555 Process bash (pid: 1643, stack limit = 0xecd60190) (cap_capable) from (kprobe_handler+0x218/0x340) (kprobe_handler) from (kprobe_trap_handler+0x24/0x48) (kprobe_trap_handler) from (do_undefinstr+0x13c/0x364) (do_undefinstr) from (__und_svc_finish+0x0/0x30) (__und_svc_finish) from (cap_capable+0x18/0xb0) (cap_capable) from (cap_vm_enough_memory+0x38/0x48) (cap_vm_enough_memory) from (security_vm_enough_memory_mm+0x48/0x6c) (security_vm_enough_memory_mm) from (copy_process.constprop.5+0x16b4/0x25c8) (copy_process.constprop.5) from (_do_fork+0xe8/0x55c) (_do_fork) from (SyS_clone+0x1c/0x24) (SyS_clone) from (__sys_trace_return+0x0/0x10) Code: 0050a0e1 6c0080e2 0140a0e1 0260a0e1 (f801f0e7) Fixes: 35aa1df ("ARM kprobes: instruction single-stepping support") Fixes: 4210157 ("ARM: 9017/2: Enable KASan for ARM") Signed-off-by: huangshaobo <huangshaobo6@huawei.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

When bringing down the netdevice or system shutdown, a panic can be triggered while accessing the sysfs path because the device is already removed. [ 755.549084] mlx5_core 0000:12:00.1: Shutdown was called [ 756.404455] mlx5_core 0000:12:00.0: Shutdown was called ... [ 757.937260] BUG: unable to handle kernel NULL pointer dereference at (null) [ 758.031397] IP: [<ffffffff8ee11acb>] dma_pool_alloc+0x1ab/0x280 crash> bt ... PID: 12649 TASK: ffff8924108f2100 CPU: 1 COMMAND: "amsd" ... #9 [ffff89240e1a38b0] page_fault at ffffffff8f38c778 [exception RIP: dma_pool_alloc+0x1ab] RIP: ffffffff8ee11acb RSP: ffff89240e1a3968 RFLAGS: 00010046 RAX: 0000000000000246 RBX: ffff89243d874100 RCX: 0000000000001000 RDX: 0000000000000000 RSI: 0000000000000246 RDI: ffff89243d874090 RBP: ffff89240e1a39c0 R8: 000000000001f080 R9: ffff8905ffc03c00 R10: ffffffffc04680d4 R11: ffffffff8edde9fd R12: 00000000000080d0 R13: ffff89243d874090 R14: ffff89243d874080 R15: 0000000000000000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #10 [ffff89240e1a39c8] mlx5_alloc_cmd_msg at ffffffffc04680f3 [mlx5_core] #11 [ffff89240e1a3a18] cmd_exec at ffffffffc046ad62 [mlx5_core] #12 [ffff89240e1a3ab8] mlx5_cmd_exec at ffffffffc046b4fb [mlx5_core] #13 [ffff89240e1a3ae8] mlx5_core_access_reg at ffffffffc0475434 [mlx5_core] #14 [ffff89240e1a3b40] mlx5e_get_fec_caps at ffffffffc04a7348 [mlx5_core] #15 [ffff89240e1a3bb0] get_fec_supported_advertised at ffffffffc04992bf [mlx5_core] #16 [ffff89240e1a3c08] mlx5e_get_link_ksettings at ffffffffc049ab36 [mlx5_core] #17 [ffff89240e1a3ce8] __ethtool_get_link_ksettings at ffffffff8f25db46 #18 [ffff89240e1a3d48] speed_show at ffffffff8f277208 #19 [ffff89240e1a3dd8] dev_attr_show at ffffffff8f0b70e3 #20 [ffff89240e1a3df8] sysfs_kf_seq_show at ffffffff8eedbedf #21 [ffff89240e1a3e18] kernfs_seq_show at ffffffff8eeda596 #22 [ffff89240e1a3e28] seq_read at ffffffff8ee76d10 #23 [ffff89240e1a3e98] kernfs_fop_read at ffffffff8eedaef5 #24 [ffff89240e1a3ed8] vfs_read at ffffffff8ee4e3ff #25 [ffff89240e1a3f08] sys_read at ffffffff8ee4f27f #26 [ffff89240e1a3f50] system_call_fastpath at ffffffff8f395f92 crash> net_device.state ffff89443b0c0000 state = 0x5 (__LINK_STATE_START| __LINK_STATE_NOCARRIER) To prevent this scenario, we also make sure that the netdevice is present. Signed-off-by: suresh kumar <suresh2514@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>

The following WARN is triggered from kvm_vm_ioctl_set_clock(): WARNING: CPU: 10 PID: 579353 at arch/x86/kvm/../../../virt/kvm/kvm_main.c:3161 mark_page_dirty_in_slot+0x6c/0x80 [kvm] ... CPU: 10 PID: 579353 Comm: qemu-system-x86 Tainted: G W O 5.16.0.stable #20 Hardware name: LENOVO 20UF001CUS/20UF001CUS, BIOS R1CET65W(1.34 ) 06/17/2021 RIP: 0010:mark_page_dirty_in_slot+0x6c/0x80 [kvm] ... Call Trace: <TASK> ? kvm_write_guest+0x114/0x120 [kvm] kvm_hv_invalidate_tsc_page+0x9e/0xf0 [kvm] kvm_arch_vm_ioctl+0xa26/0xc50 [kvm] ? schedule+0x4e/0xc0 ? __cond_resched+0x1a/0x50 ? futex_wait+0x166/0x250 ? __send_signal+0x1f1/0x3d0 kvm_vm_ioctl+0x747/0xda0 [kvm] ... The WARN was introduced by commit 03c0304a86bc ("KVM: Warn if mark_page_dirty() is called without an active vCPU") but the change seems to be correct (unlike Hyper-V TSC page update mechanism). In fact, there's no real need to actually write to guest memory to invalidate TSC page, this can be done by the first vCPU which goes through kvm_guest_time_update(). Reported-by: Maxim Levitsky <mlevitsk@redhat.com> Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> Suggested-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20220407201013.963226-1-vkuznets@redhat.com>

When a system with E810 with existing VFs gets rebooted the following hang may be observed. Pid 1 is hung in iavf_remove(), part of a network driver: PID: 1 TASK: ffff965400e5a340 CPU: 24 COMMAND: "systemd-shutdow" #0 [ffffaad04005fa50] __schedule at ffffffff8b3239cb ceph#1 [ffffaad04005fae8] schedule at ffffffff8b323e2d ceph#2 [ffffaad04005fb00] schedule_hrtimeout_range_clock at ffffffff8b32cebc ceph#3 [ffffaad04005fb80] usleep_range_state at ffffffff8b32c930 #4 [ffffaad04005fbb0] iavf_remove at ffffffffc12b9b4c [iavf] ceph#5 [ffffaad04005fbf0] pci_device_remove at ffffffff8add7513 ceph#6 [ffffaad04005fc10] device_release_driver_internal at ffffffff8af08baa ceph#7 [ffffaad04005fc40] pci_stop_bus_device at ffffffff8adcc5fc ceph#8 [ffffaad04005fc60] pci_stop_and_remove_bus_device at ffffffff8adcc81e ceph#9 [ffffaad04005fc70] pci_iov_remove_virtfn at ffffffff8adf9429 ceph#10 [ffffaad04005fca8] sriov_disable at ffffffff8adf98e4 ceph#11 [ffffaad04005fcc8] ice_free_vfs at ffffffffc04bb2c8 [ice] ceph#12 [ffffaad04005fd10] ice_remove at ffffffffc04778fe [ice] ceph#13 [ffffaad04005fd38] ice_shutdown at ffffffffc0477946 [ice] ceph#14 [ffffaad04005fd50] pci_device_shutdown at ffffffff8add58f1 ceph#15 [ffffaad04005fd70] device_shutdown at ffffffff8af05386 ceph#16 [ffffaad04005fd98] kernel_restart at ffffffff8a92a870 ceph#17 [ffffaad04005fda8] __do_sys_reboot at ffffffff8a92abd6 #18 [ffffaad04005fee0] do_syscall_64 at ffffffff8b317159 ceph#19 [ffffaad04005ff08] __context_tracking_enter at ffffffff8b31b6fc ceph#20 [ffffaad04005ff18] syscall_exit_to_user_mode at ffffffff8b31b50d ceph#21 [ffffaad04005ff28] do_syscall_64 at ffffffff8b317169 ceph#22 [ffffaad04005ff50] entry_SYSCALL_64_after_hwframe at ffffffff8b40009b RIP: 00007f1baa5c13d7 RSP: 00007fffbcc55a98 RFLAGS: 00000202 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1baa5c13d7 RDX: 0000000001234567 RSI: 0000000028121969 RDI: 00000000fee1dead RBP: 00007fffbcc55ca0 R8: 0000000000000000 R9: 00007fffbcc54e90 R10: 00007fffbcc55050 R11: 0000000000000202 R12: 0000000000000005 R13: 0000000000000000 R14: 00007fffbcc55af0 R15: 0000000000000000 ORIG_RAX: 00000000000000a9 CS: 0033 SS: 002b During reboot all drivers PM shutdown callbacks are invoked. In iavf_shutdown() the adapter state is changed to __IAVF_REMOVE. In ice_shutdown() the call chain above is executed, which at some point calls iavf_remove(). However iavf_remove() expects the VF to be in one of the states __IAVF_RUNNING, __IAVF_DOWN or __IAVF_INIT_FAILED. If that's not the case it sleeps forever. So if iavf_shutdown() gets invoked before iavf_remove() the system will hang indefinitely because the adapter is already in state __IAVF_REMOVE. Fix this by returning from iavf_remove() if the state is __IAVF_REMOVE, as we already went through iavf_shutdown(). Fixes: 9745780 ("iavf: Add waiting so the port is initialized in remove") Fixes: a841733 ("iavf: Fix race condition between iavf_shutdown and iavf_remove") Reported-by: Marius Cornea <mcornea@redhat.com> Signed-off-by: Stefan Assmann <sassmann@kpanic.de> Reviewed-by: Michal Kubiak <michal.kubiak@intel.com> Tested-by: Rafal Romanowski <rafal.romanowski@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

…_write() If a user can make copy_from_user() fail, there is a potential for UAF/DF due to a lack of locking around the allocation, use and freeing of the data buffers. This issue is not theoretical. I managed to author a POC for it: BUG: KASAN: double-free in kfree+0x5c/0xac Free of addr ffff29280be5de00 by task poc/356 CPU: 1 PID: 356 Comm: poc Not tainted 6.1.0-00001-g961aa6552c04-dirty #20 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace.part.0+0xe0/0xf0 show_stack+0x18/0x40 dump_stack_lvl+0x64/0x80 print_report+0x188/0x48c kasan_report_invalid_free+0xa0/0xc0 ____kasan_slab_free+0x174/0x1b0 __kasan_slab_free+0x18/0x24 __kmem_cache_free+0x130/0x2e0 kfree+0x5c/0xac mbox_test_message_write+0x208/0x29c full_proxy_write+0x90/0xf0 vfs_write+0x154/0x440 ksys_write+0xcc/0x180 __arm64_sys_write+0x44/0x60 invoke_syscall+0x60/0x190 el0_svc_common.constprop.0+0x7c/0x160 do_el0_svc+0x40/0xf0 el0_svc+0x2c/0x6c el0t_64_sync_handler+0xf4/0x120 el0t_64_sync+0x18c/0x190 Allocated by task 356: kasan_save_stack+0x3c/0x70 kasan_set_track+0x2c/0x40 kasan_save_alloc_info+0x24/0x34 __kasan_kmalloc+0xb8/0xc0 kmalloc_trace+0x58/0x70 mbox_test_message_write+0x6c/0x29c full_proxy_write+0x90/0xf0 vfs_write+0x154/0x440 ksys_write+0xcc/0x180 __arm64_sys_write+0x44/0x60 invoke_syscall+0x60/0x190 el0_svc_common.constprop.0+0x7c/0x160 do_el0_svc+0x40/0xf0 el0_svc+0x2c/0x6c el0t_64_sync_handler+0xf4/0x120 el0t_64_sync+0x18c/0x190 Freed by task 357: kasan_save_stack+0x3c/0x70 kasan_set_track+0x2c/0x40 kasan_save_free_info+0x38/0x5c ____kasan_slab_free+0x13c/0x1b0 __kasan_slab_free+0x18/0x24 __kmem_cache_free+0x130/0x2e0 kfree+0x5c/0xac mbox_test_message_write+0x208/0x29c full_proxy_write+0x90/0xf0 vfs_write+0x154/0x440 ksys_write+0xcc/0x180 __arm64_sys_write+0x44/0x60 invoke_syscall+0x60/0x190 el0_svc_common.constprop.0+0x7c/0x160 do_el0_svc+0x40/0xf0 el0_svc+0x2c/0x6c el0t_64_sync_handler+0xf4/0x120 el0t_64_sync+0x18c/0x190 Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

The cited commit adds a compeletion to remove dependency on rtnl lock. But it causes a deadlock for multiple encapsulations: crash> bt ffff8aece8a64000 PID: 1514557 TASK: ffff8aece8a64000 CPU: 3 COMMAND: "tc" #0 [ffffa6d14183f368] __schedule at ffffffffb8ba7f45 #1 [ffffa6d14183f3f8] schedule at ffffffffb8ba8418 #2 [ffffa6d14183f418] schedule_preempt_disabled at ffffffffb8ba8898 #3 [ffffa6d14183f428] __mutex_lock at ffffffffb8baa7f8 #4 [ffffa6d14183f4d0] mutex_lock_nested at ffffffffb8baabeb #5 [ffffa6d14183f4e0] mlx5e_attach_encap at ffffffffc0f48c17 [mlx5_core] #6 [ffffa6d14183f628] mlx5e_tc_add_fdb_flow at ffffffffc0f39680 [mlx5_core] #7 [ffffa6d14183f688] __mlx5e_add_fdb_flow at ffffffffc0f3b636 [mlx5_core] #8 [ffffa6d14183f6f0] mlx5e_tc_add_flow at ffffffffc0f3bcdf [mlx5_core] #9 [ffffa6d14183f728] mlx5e_configure_flower at ffffffffc0f3c1d1 [mlx5_core] #10 [ffffa6d14183f790] mlx5e_rep_setup_tc_cls_flower at ffffffffc0f3d529 [mlx5_core] #11 [ffffa6d14183f7a0] mlx5e_rep_setup_tc_cb at ffffffffc0f3d714 [mlx5_core] #12 [ffffa6d14183f7b0] tc_setup_cb_add at ffffffffb8931bb8 #13 [ffffa6d14183f810] fl_hw_replace_filter at ffffffffc0dae901 [cls_flower] #14 [ffffa6d14183f8d8] fl_change at ffffffffc0db5c57 [cls_flower] #15 [ffffa6d14183f970] tc_new_tfilter at ffffffffb8936047 #16 [ffffa6d14183fac8] rtnetlink_rcv_msg at ffffffffb88c7c31 #17 [ffffa6d14183fb50] netlink_rcv_skb at ffffffffb8942853 #18 [ffffa6d14183fbc0] rtnetlink_rcv at ffffffffb88c1835 #19 [ffffa6d14183fbd0] netlink_unicast at ffffffffb8941f27 #20 [ffffa6d14183fc18] netlink_sendmsg at ffffffffb8942245 #21 [ffffa6d14183fc98] sock_sendmsg at ffffffffb887d482 #22 [ffffa6d14183fcb8] ____sys_sendmsg at ffffffffb887d81a #23 [ffffa6d14183fd38] ___sys_sendmsg at ffffffffb88806e2 #24 [ffffa6d14183fe90] __sys_sendmsg at ffffffffb88807a2 #25 [ffffa6d14183ff28] __x64_sys_sendmsg at ffffffffb888080f #26 [ffffa6d14183ff38] do_syscall_64 at ffffffffb8b9b6a8 #27 [ffffa6d14183ff50] entry_SYSCALL_64_after_hwframe at ffffffffb8c0007c crash> bt 0xffff8aeb07544000 PID: 1110766 TASK: ffff8aeb07544000 CPU: 0 COMMAND: "kworker/u20:9" #0 [ffffa6d14e6b7bd8] __schedule at ffffffffb8ba7f45 #1 [ffffa6d14e6b7c68] schedule at ffffffffb8ba8418 #2 [ffffa6d14e6b7c88] schedule_timeout at ffffffffb8baef88 #3 [ffffa6d14e6b7d10] wait_for_completion at ffffffffb8ba968b #4 [ffffa6d14e6b7d60] mlx5e_take_all_encap_flows at ffffffffc0f47ec4 [mlx5_core] #5 [ffffa6d14e6b7da0] mlx5e_rep_update_flows at ffffffffc0f3e734 [mlx5_core] #6 [ffffa6d14e6b7df8] mlx5e_rep_neigh_update at ffffffffc0f400bb [mlx5_core] #7 [ffffa6d14e6b7e50] process_one_work at ffffffffb80acc9c #8 [ffffa6d14e6b7ed0] worker_thread at ffffffffb80ad012 #9 [ffffa6d14e6b7f10] kthread at ffffffffb80b615d #10 [ffffa6d14e6b7f50] ret_from_fork at ffffffffb8001b2f After the first encap is attached, flow will be added to encap entry's flows list. If neigh update is running at this time, the following encaps of the flow can't hold the encap_tbl_lock and sleep. If neigh update thread is waiting for that flow's init_done, deadlock happens. Fix it by holding lock outside of the for loop. If neigh update is running, prevent encap flows from offloading. Since the lock is held outside of the for loop, concurrent creation of encap entries is not allowed. So remove unnecessary wait_for_completion call for res_ready. Fixes: 95435ad ("net/mlx5e: Only access fully initialized flows in neigh update") Signed-off-by: Chris Mi <cmi@nvidia.com> Reviewed-by: Roi Dayan <roid@nvidia.com> Reviewed-by: Vlad Buslov <vladbu@nvidia.com> Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Christoph reported a divide by zero bug in mptcp_recvmsg(): divide error: 0000 [#1] PREEMPT SMP CPU: 1 PID: 19978 Comm: syz-executor.6 Not tainted 6.4.0-rc2-gffcc7899081b #20 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014 RIP: 0010:__tcp_select_window+0x30e/0x420 net/ipv4/tcp_output.c:3018 Code: 11 ff 0f b7 cd c1 e9 0c b8 ff ff ff ff d3 e0 89 c1 f7 d1 01 cb 21 c3 eb 17 e8 2e 83 11 ff 31 db eb 0e e8 25 83 11 ff 89 d8 99 <f7> 7c 24 04 29 d3 65 48 8b 04 25 28 00 00 00 48 3b 44 24 10 75 60 RSP: 0018:ffffc90000a07a18 EFLAGS: 00010246 RAX: 000000000000ffd7 RBX: 000000000000ffd7 RCX: 0000000000040000 RDX: 0000000000000000 RSI: 000000000003ffff RDI: 0000000000040000 RBP: 000000000000ffd7 R08: ffffffff820cf297 R09: 0000000000000001 R10: 0000000000000000 R11: ffffffff8103d1a0 R12: 0000000000003f00 R13: 0000000000300000 R14: ffff888101cf3540 R15: 0000000000180000 FS: 00007f9af4c09640(0000) GS:ffff88813bd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b33824000 CR3: 000000012f241001 CR4: 0000000000170ee0 Call Trace: <TASK> __tcp_cleanup_rbuf+0x138/0x1d0 net/ipv4/tcp.c:1611 mptcp_recvmsg+0xcb8/0xdd0 net/mptcp/protocol.c:2034 inet_recvmsg+0x127/0x1f0 net/ipv4/af_inet.c:861 ____sys_recvmsg+0x269/0x2b0 net/socket.c:1019 ___sys_recvmsg+0xe6/0x260 net/socket.c:2764 do_recvmmsg+0x1a5/0x470 net/socket.c:2858 __do_sys_recvmmsg net/socket.c:2937 [inline] __se_sys_recvmmsg net/socket.c:2953 [inline] __x64_sys_recvmmsg+0xa6/0x130 net/socket.c:2953 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x47/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7f9af58fc6a9 Code: 5c c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 4f 37 0d 00 f7 d8 64 89 01 48 RSP: 002b:00007f9af4c08cd8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00000000006bc050 RCX: 00007f9af58fc6a9 RDX: 0000000000000001 RSI: 0000000020000140 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000f00 R11: 0000000000000246 R12: 00000000006bc05c R13: fffffffffffffea8 R14: 00000000006bc050 R15: 000000000001fe40 </TASK> mptcp_recvmsg is allowed to release the msk socket lock when blocking, and before re-acquiring it another thread could have switched the sock to TCP_LISTEN status - with a prior connect(AF_UNSPEC) - also clearing icsk_ack.rcv_mss. Address the issue preventing the disconnect if some other process is concurrently performing a blocking syscall on the same socket, alike commit 4faeee0 ("tcp: deny tcp_disconnect() when threads are waiting"). Fixes: a6b118f ("mptcp: add receive buffer auto-tuning") Cc: stable@vger.kernel.org Reported-by: Christoph Paasch <cpaasch@apple.com> Closes: multipath-tcp/mptcp_net-next#404 Signed-off-by: Paolo Abeni <pabeni@redhat.com> Tested-by: Christoph Paasch <cpaasch@apple.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org>

The pointer to mdev_bus_compat_class is statically defined at the top of mdev_core, and was originally (commit 7b96953 ("vfio: Mediated device Core driver") serialized by the parent_list_lock. The blamed commit removed this mutex, leaving the pointer initialization unserialized. As a result, the creation of multiple MDEVs in parallel (such as during boot) can encounter errors during the creation of the sysfs entries, such as: [ 8.337509] sysfs: cannot create duplicate filename '/class/mdev_bus' [ 8.337514] vfio_ccw 0.0.01d8: MDEV: Registered [ 8.337516] CPU: 13 PID: 946 Comm: driverctl Not tainted 6.4.0-rc7 #20 [ 8.337522] Hardware name: IBM 3906 M05 780 (LPAR) [ 8.337525] Call Trace: [ 8.337528] [<0000000162b0145a>] dump_stack_lvl+0x62/0x80 [ 8.337540] [<00000001622aeb30>] sysfs_warn_dup+0x78/0x88 [ 8.337549] [<00000001622aeca6>] sysfs_create_dir_ns+0xe6/0xf8 [ 8.337552] [<0000000162b04504>] kobject_add_internal+0xf4/0x340 [ 8.337557] [<0000000162b04d48>] kobject_add+0x78/0xd0 [ 8.337561] [<0000000162b04e0a>] kobject_create_and_add+0x6a/0xb8 [ 8.337565] [<00000001627a110e>] class_compat_register+0x5e/0x90 [ 8.337572] [<000003ff7fd815da>] mdev_register_parent+0x102/0x130 [mdev] [ 8.337581] [<000003ff7fdc7f2c>] vfio_ccw_sch_probe+0xe4/0x178 [vfio_ccw] [ 8.337588] [<0000000162a7833c>] css_probe+0x44/0x80 [ 8.337599] [<000000016279f4da>] really_probe+0xd2/0x460 [ 8.337603] [<000000016279fa08>] driver_probe_device+0x40/0xf0 [ 8.337606] [<000000016279fb78>] __device_attach_driver+0xc0/0x140 [ 8.337610] [<000000016279cbe0>] bus_for_each_drv+0x90/0xd8 [ 8.337618] [<00000001627a00b0>] __device_attach+0x110/0x190 [ 8.337621] [<000000016279c7c8>] bus_rescan_devices_helper+0x60/0xb0 [ 8.337626] [<000000016279cd48>] drivers_probe_store+0x48/0x80 [ 8.337632] [<00000001622ac9b0>] kernfs_fop_write_iter+0x138/0x1f0 [ 8.337635] [<00000001621e5e14>] vfs_write+0x1ac/0x2f8 [ 8.337645] [<00000001621e61d8>] ksys_write+0x70/0x100 [ 8.337650] [<0000000162b2bdc4>] __do_syscall+0x1d4/0x200 [ 8.337656] [<0000000162b3c828>] system_call+0x70/0x98 [ 8.337664] kobject: kobject_add_internal failed for mdev_bus with -EEXIST, don't try to register things with the same name in the same directory. [ 8.337668] kobject: kobject_create_and_add: kobject_add error: -17 [ 8.337674] vfio_ccw: probe of 0.0.01d9 failed with error -12 [ 8.342941] vfio_ccw_mdev aeb9ca91-10c6-42bc-a168-320023570aea: Adding to iommu group 2 Move the initialization of the mdev_bus_compat_class pointer to the init path, to match the cleanup in module exit. This way the code in mdev_register_parent() can simply link the new parent to it, rather than determining whether initialization is required first. Fixes: 89345d5 ("vfio/mdev: embedd struct mdev_parent in the parent data structure") Reported-by: Alexander Egorenkov <egorenar@linux.ibm.com> Signed-off-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20230626133642.2939168-1-farman@linux.ibm.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

The following processes run into a deadlock. CPU 41 was waiting for CPU 29 to handle a CSD request while holding spinlock "crashdump_lock", but CPU 29 was hung by that spinlock with IRQs disabled. PID: 17360 TASK: ffff95c1090c5c40 CPU: 41 COMMAND: "mrdiagd" !# 0 [ffffb80edbf37b58] __read_once_size at ffffffff9b871a40 include/linux/compiler.h:185:0 !# 1 [ffffb80edbf37b58] atomic_read at ffffffff9b871a40 arch/x86/include/asm/atomic.h:27:0 !# 2 [ffffb80edbf37b58] dump_stack at ffffffff9b871a40 lib/dump_stack.c:54:0 # 3 [ffffb80edbf37b78] csd_lock_wait_toolong at ffffffff9b131ad5 kernel/smp.c:364:0 # 4 [ffffb80edbf37b78] __csd_lock_wait at ffffffff9b131ad5 kernel/smp.c:384:0 # 5 [ffffb80edbf37bf8] csd_lock_wait at ffffffff9b13267a kernel/smp.c:394:0 # 6 [ffffb80edbf37bf8] smp_call_function_many at ffffffff9b13267a kernel/smp.c:843:0 # 7 [ffffb80edbf37c50] smp_call_function at ffffffff9b13279d kernel/smp.c:867:0 # 8 [ffffb80edbf37c50] on_each_cpu at ffffffff9b13279d kernel/smp.c:976:0 # 9 [ffffb80edbf37c78] flush_tlb_kernel_range at ffffffff9b085c4b arch/x86/mm/tlb.c:742:0 #10 [ffffb80edbf37cb8] __purge_vmap_area_lazy at ffffffff9b23a1e0 mm/vmalloc.c:701:0 #11 [ffffb80edbf37ce0] try_purge_vmap_area_lazy at ffffffff9b23a2cc mm/vmalloc.c:722:0 #12 [ffffb80edbf37ce0] free_vmap_area_noflush at ffffffff9b23a2cc mm/vmalloc.c:754:0 #13 [ffffb80edbf37cf8] free_unmap_vmap_area at ffffffff9b23bb3b mm/vmalloc.c:764:0 #14 [ffffb80edbf37cf8] remove_vm_area at ffffffff9b23bb3b mm/vmalloc.c:1509:0 #15 [ffffb80edbf37d18] __vunmap at ffffffff9b23bb8a mm/vmalloc.c:1537:0 #16 [ffffb80edbf37d40] vfree at ffffffff9b23bc85 mm/vmalloc.c:1612:0 #17 [ffffb80edbf37d58] megasas_free_host_crash_buffer [megaraid_sas] at ffffffffc020b7f2 drivers/scsi/megaraid/megaraid_sas_fusion.c:3932:0 #18 [ffffb80edbf37d80] fw_crash_state_store [megaraid_sas] at ffffffffc01f804d drivers/scsi/megaraid/megaraid_sas_base.c:3291:0 #19 [ffffb80edbf37dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0 #20 [ffffb80edbf37dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0 #21 [ffffb80edbf37de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0 #22 [ffffb80edbf37e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0 #23 [ffffb80edbf37ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0 #24 [ffffb80edbf37ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0 #25 [ffffb80edbf37ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0 #26 [ffffb80edbf37f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0 #27 [ffffb80edbf37f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0 PID: 17355 TASK: ffff95c1090c3d80 CPU: 29 COMMAND: "mrdiagd" !# 0 [ffffb80f2d3c7d30] __read_once_size at ffffffff9b0f2ab0 include/linux/compiler.h:185:0 !# 1 [ffffb80f2d3c7d30] native_queued_spin_lock_slowpath at ffffffff9b0f2ab0 kernel/locking/qspinlock.c:368:0 # 2 [ffffb80f2d3c7d58] pv_queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/paravirt.h:674:0 # 3 [ffffb80f2d3c7d58] queued_spin_lock_slowpath at ffffffff9b0f244b arch/x86/include/asm/qspinlock.h:53:0 # 4 [ffffb80f2d3c7d68] queued_spin_lock at ffffffff9b8961a6 include/asm-generic/qspinlock.h:90:0 # 5 [ffffb80f2d3c7d68] do_raw_spin_lock_flags at ffffffff9b8961a6 include/linux/spinlock.h:173:0 # 6 [ffffb80f2d3c7d68] __raw_spin_lock_irqsave at ffffffff9b8961a6 include/linux/spinlock_api_smp.h:122:0 # 7 [ffffb80f2d3c7d68] _raw_spin_lock_irqsave at ffffffff9b8961a6 kernel/locking/spinlock.c:160:0 # 8 [ffffb80f2d3c7d88] fw_crash_buffer_store [megaraid_sas] at ffffffffc01f8129 drivers/scsi/megaraid/megaraid_sas_base.c:3205:0 # 9 [ffffb80f2d3c7dc0] dev_attr_store at ffffffff9b56dd7b drivers/base/core.c:758:0 #10 [ffffb80f2d3c7dd0] sysfs_kf_write at ffffffff9b326acf fs/sysfs/file.c:144:0 #11 [ffffb80f2d3c7de0] kernfs_fop_write at ffffffff9b325fd4 fs/kernfs/file.c:316:0 #12 [ffffb80f2d3c7e20] __vfs_write at ffffffff9b29418a fs/read_write.c:480:0 #13 [ffffb80f2d3c7ea8] vfs_write at ffffffff9b294462 fs/read_write.c:544:0 #14 [ffffb80f2d3c7ee8] SYSC_write at ffffffff9b2946ec fs/read_write.c:590:0 #15 [ffffb80f2d3c7ee8] SyS_write at ffffffff9b2946ec fs/read_write.c:582:0 #16 [ffffb80f2d3c7f30] do_syscall_64 at ffffffff9b003ca9 arch/x86/entry/common.c:298:0 #17 [ffffb80f2d3c7f58] entry_SYSCALL_64 at ffffffff9ba001b1 arch/x86/entry/entry_64.S:238:0 The lock is used to synchronize different sysfs operations, it doesn't protect any resource that will be touched by an interrupt. Consequently it's not required to disable IRQs. Replace the spinlock with a mutex to fix the deadlock. Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Link: https://lore.kernel.org/r/20230828221018.19471-1-junxiao.bi@oracle.com Reviewed-by: Mike Christie <michael.christie@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Inject fault while probing mdpy.ko, if kstrdup() of create_dir() fails in kobject_add_internal() in kobject_init_and_add() in mdev_type_add() in parent_create_sysfs_files(), it will return 0 and probe successfully. And when rmmod mdpy.ko, the mdpy_dev_exit() will call mdev_unregister_parent(), the mdev_type_remove() may traverse uninitialized parent->types[i] in parent_remove_sysfs_files(), and it will cause below null-ptr-deref. If mdev_type_add() fails, return the error code and kset_unregister() to fix the issue. general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 2 PID: 10215 Comm: rmmod Tainted: G W N 6.6.0-rc2+ #20 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:__kobject_del+0x62/0x1c0 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 51 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 6b 28 48 8d 7d 10 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 24 01 00 00 48 8b 75 10 48 89 df 48 8d 6b 3c e8 RSP: 0018:ffff88810695fd30 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffffffffa0270268 RCX: 0000000000000000 RDX: 0000000000000002 RSI: 0000000000000004 RDI: 0000000000000010 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10233a4ef1 R10: ffff888119d2778b R11: 0000000063666572 R12: 0000000000000000 R13: fffffbfff404e2d4 R14: dffffc0000000000 R15: ffffffffa0271660 FS: 00007fbc81981540(0000) GS:ffff888119d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc14a142dc0 CR3: 0000000110a62003 CR4: 0000000000770ee0 DR0: ffffffff8fb0bce8 DR1: ffffffff8fb0bce9 DR2: ffffffff8fb0bcea DR3: ffffffff8fb0bceb DR6: 00000000fffe0ff0 DR7: 0000000000000600 PKRU: 55555554 Call Trace: <TASK> ? die_addr+0x3d/0xa0 ? exc_general_protection+0x144/0x220 ? asm_exc_general_protection+0x22/0x30 ? __kobject_del+0x62/0x1c0 kobject_del+0x32/0x50 parent_remove_sysfs_files+0xd6/0x170 [mdev] mdev_unregister_parent+0xfb/0x190 [mdev] ? mdev_register_parent+0x270/0x270 [mdev] ? find_module_all+0x9d/0xe0 mdpy_dev_exit+0x17/0x63 [mdpy] __do_sys_delete_module.constprop.0+0x2fa/0x4b0 ? module_flags+0x300/0x300 ? __fput+0x4e7/0xa00 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7fbc813221b7 Code: 73 01 c3 48 8b 0d d1 8c 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 b0 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 8c 2c 00 f7 d8 64 89 01 48 RSP: 002b:00007ffe780e0648 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0 RAX: ffffffffffffffda RBX: 00007ffe780e06a8 RCX: 00007fbc813221b7 RDX: 000000000000000a RSI: 0000000000000800 RDI: 000055e214df9b58 RBP: 000055e214df9af0 R08: 00007ffe780df5c1 R09: 0000000000000000 R10: 00007fbc8139ecc0 R11: 0000000000000206 R12: 00007ffe780e0870 R13: 00007ffe780e0ed0 R14: 000055e214df9260 R15: 000055e214df9af0 </TASK> Modules linked in: mdpy(-) mdev vfio_iommu_type1 vfio [last unloaded: mdpy] Dumping ftrace buffer: (ftrace buffer empty) ---[ end trace 0000000000000000 ]--- RIP: 0010:__kobject_del+0x62/0x1c0 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 51 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 6b 28 48 8d 7d 10 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 24 01 00 00 48 8b 75 10 48 89 df 48 8d 6b 3c e8 RSP: 0018:ffff88810695fd30 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffffffffa0270268 RCX: 0000000000000000 RDX: 0000000000000002 RSI: 0000000000000004 RDI: 0000000000000010 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10233a4ef1 R10: ffff888119d2778b R11: 0000000063666572 R12: 0000000000000000 R13: fffffbfff404e2d4 R14: dffffc0000000000 R15: ffffffffa0271660 FS: 00007fbc81981540(0000) GS:ffff888119d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc14a142dc0 CR3: 0000000110a62003 CR4: 0000000000770ee0 DR0: ffffffff8fb0bce8 DR1: ffffffff8fb0bce9 DR2: ffffffff8fb0bcea DR3: ffffffff8fb0bceb DR6: 00000000fffe0ff0 DR7: 0000000000000600 PKRU: 55555554 Kernel panic - not syncing: Fatal exception Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 1 seconds.. Fixes: da44c34 ("vfio/mdev: simplify mdev_type handling") Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Reviewed-by: Eric Farman <farman@linux.ibm.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/20230918115551.1423193-1-ruanjinjie@huawei.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

The following call trace shows a deadlock issue due to recursive locking of mutex "device_mutex". First lock acquire is in target_for_each_device() and second in target_free_device(). PID: 148266 TASK: ffff8be21ffb5d00 CPU: 10 COMMAND: "iscsi_ttx" #0 [ffffa2bfc9ec3b18] __schedule at ffffffffa8060e7f #1 [ffffa2bfc9ec3ba0] schedule at ffffffffa8061224 #2 [ffffa2bfc9ec3bb8] schedule_preempt_disabled at ffffffffa80615ee #3 [ffffa2bfc9ec3bc8] __mutex_lock at ffffffffa8062fd7 #4 [ffffa2bfc9ec3c40] __mutex_lock_slowpath at ffffffffa80631d3 #5 [ffffa2bfc9ec3c50] mutex_lock at ffffffffa806320c #6 [ffffa2bfc9ec3c68] target_free_device at ffffffffc0935998 [target_core_mod] #7 [ffffa2bfc9ec3c90] target_core_dev_release at ffffffffc092f975 [target_core_mod] #8 [ffffa2bfc9ec3ca0] config_item_put at ffffffffa79d250f #9 [ffffa2bfc9ec3cd0] config_item_put at ffffffffa79d2583 #10 [ffffa2bfc9ec3ce0] target_devices_idr_iter at ffffffffc0933f3a [target_core_mod] #11 [ffffa2bfc9ec3d00] idr_for_each at ffffffffa803f6fc #12 [ffffa2bfc9ec3d60] target_for_each_device at ffffffffc0935670 [target_core_mod] #13 [ffffa2bfc9ec3d98] transport_deregister_session at ffffffffc0946408 [target_core_mod] #14 [ffffa2bfc9ec3dc8] iscsit_close_session at ffffffffc09a44a6 [iscsi_target_mod] #15 [ffffa2bfc9ec3df0] iscsit_close_connection at ffffffffc09a4a88 [iscsi_target_mod] #16 [ffffa2bfc9ec3df8] finish_task_switch at ffffffffa76e5d07 #17 [ffffa2bfc9ec3e78] iscsit_take_action_for_connection_exit at ffffffffc0991c23 [iscsi_target_mod] #18 [ffffa2bfc9ec3ea0] iscsi_target_tx_thread at ffffffffc09a403b [iscsi_target_mod] #19 [ffffa2bfc9ec3f08] kthread at ffffffffa76d8080 #20 [ffffa2bfc9ec3f50] ret_from_fork at ffffffffa8200364 Fixes: 36d4cb4 ("scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion") Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com> Link: https://lore.kernel.org/r/20230918225848.66463-1-junxiao.bi@oracle.com Reviewed-by: Mike Christie <michael.christie@oracle.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

When creating ceq_0 during probing irdma, cqp.sc_cqp will be sent as a cqp_request to cqp->sc_cqp.sq_ring. If the request is pending when removing the irdma driver or unplugging its aux device, cqp.sc_cqp will be dereferenced as wrong struct in irdma_free_pending_cqp_request(). PID: 3669 TASK: ffff88aef892c000 CPU: 28 COMMAND: "kworker/28:0" #0 [fffffe0000549e38] crash_nmi_callback at ffffffff810e3a34 #1 [fffffe0000549e40] nmi_handle at ffffffff810788b2 #2 [fffffe0000549ea0] default_do_nmi at ffffffff8107938f #3 [fffffe0000549eb8] do_nmi at ffffffff81079582 #4 [fffffe0000549ef0] end_repeat_nmi at ffffffff82e016b4 [exception RIP: native_queued_spin_lock_slowpath+1291] RIP: ffffffff8127e72b RSP: ffff88aa841ef778 RFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff88b01f849700 RCX: ffffffff8127e47e RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff83857ec0 RBP: ffff88afe3e4efc8 R8: ffffed15fc7c9dfa R9: ffffed15fc7c9dfa R10: 0000000000000001 R11: ffffed15fc7c9df9 R12: 0000000000740000 R13: ffff88b01f849708 R14: 0000000000000003 R15: ffffed1603f092e1 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0000 -- <NMI exception stack> -- #5 [ffff88aa841ef778] native_queued_spin_lock_slowpath at ffffffff8127e72b #6 [ffff88aa841ef7b0] _raw_spin_lock_irqsave at ffffffff82c22aa4 #7 [ffff88aa841ef7c8] __wake_up_common_lock at ffffffff81257363 #8 [ffff88aa841ef888] irdma_free_pending_cqp_request at ffffffffa0ba12cc [irdma] #9 [ffff88aa841ef958] irdma_cleanup_pending_cqp_op at ffffffffa0ba1469 [irdma] #10 [ffff88aa841ef9c0] irdma_ctrl_deinit_hw at ffffffffa0b2989f [irdma] #11 [ffff88aa841efa28] irdma_remove at ffffffffa0b252df [irdma] #12 [ffff88aa841efae8] auxiliary_bus_remove at ffffffff8219afdb #13 [ffff88aa841efb00] device_release_driver_internal at ffffffff821882e6 #14 [ffff88aa841efb38] bus_remove_device at ffffffff82184278 #15 [ffff88aa841efb88] device_del at ffffffff82179d23 #16 [ffff88aa841efc48] ice_unplug_aux_dev at ffffffffa0eb1c14 [ice] #17 [ffff88aa841efc68] ice_service_task at ffffffffa0d88201 [ice] #18 [ffff88aa841efde8] process_one_work at ffffffff811c589a #19 [ffff88aa841efe60] worker_thread at ffffffff811c71ff #20 [ffff88aa841eff10] kthread at ffffffff811d87a0 #21 [ffff88aa841eff50] ret_from_fork at ffffffff82e0022f Fixes: 44d9e52 ("RDMA/irdma: Implement device initialization definitions") Link: https://lore.kernel.org/r/20231130081415.891006-1-lishifeng@sangfor.com.cn Suggested-by: "Ismail, Mustafa" <mustafa.ismail@intel.com> Signed-off-by: Shifeng Li <lishifeng@sangfor.com.cn> Reviewed-by: Shiraz Saleem <shiraz.saleem@intel.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

When running autonuma with enabling multi-size THP, I encountered the following kernel crash issue: [ 134.290216] list_del corruption. prev->next should be fffff9ad42e1c490, but was dead000000000100. (prev=fffff9ad42399890) [ 134.290877] kernel BUG at lib/list_debug.c:62! [ 134.291052] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI [ 134.291210] CPU: 56 PID: 8037 Comm: numa01 Kdump: loaded Tainted: G E 6.7.0-rc4+ #20 [ 134.291649] RIP: 0010:__list_del_entry_valid_or_report+0x97/0xb0 ...... [ 134.294252] Call Trace: [ 134.294362] <TASK> [ 134.294440] ? die+0x33/0x90 [ 134.294561] ? do_trap+0xe0/0x110 ...... [ 134.295681] ? __list_del_entry_valid_or_report+0x97/0xb0 [ 134.295842] folio_undo_large_rmappable+0x99/0x100 [ 134.296003] destroy_large_folio+0x68/0x70 [ 134.296172] migrate_folio_move+0x12e/0x260 [ 134.296264] ? __pfx_remove_migration_pte+0x10/0x10 [ 134.296389] migrate_pages_batch+0x495/0x6b0 [ 134.296523] migrate_pages+0x1d0/0x500 [ 134.296646] ? __pfx_alloc_misplaced_dst_folio+0x10/0x10 [ 134.296799] migrate_misplaced_folio+0x12d/0x2b0 [ 134.296953] do_numa_page+0x1f4/0x570 [ 134.297121] __handle_mm_fault+0x2b0/0x6c0 [ 134.297254] handle_mm_fault+0x107/0x270 [ 134.300897] do_user_addr_fault+0x167/0x680 [ 134.304561] exc_page_fault+0x65/0x140 [ 134.307919] asm_exc_page_fault+0x22/0x30 The reason for the crash is that, the commit 85ce2c5 ("memcontrol: only transfer the memcg data for migration") removed the charging and uncharging operations of the migration folios and cleared the memcg data of the old folio. During the subsequent release process of the old large folio in destroy_large_folio(), if the large folio needs to be removed from the split queue, an incorrect split queue can be obtained (which is pgdat->deferred_split_queue) because the old folio's memcg is NULL now. This can lead to list operations being performed under the wrong split queue lock protection, resulting in a list crash as above. After the migration, the old folio is going to be freed, so we can remove it from the split queue in mem_cgroup_migrate() a bit earlier before clearing the memcg data to avoid getting incorrect split queue. [akpm@linux-foundation.org: fix comment, per Zi Yan] Link: https://lkml.kernel.org/r/61273e5e9b490682388377c20f52d19de4a80460.1703054559.git.baolin.wang@linux.alibaba.com Fixes: 85ce2c5 ("memcontrol: only transfer the memcg data for migration") Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: Nhat Pham <nphamcs@gmail.com> Reviewed-by: Yang Shi <shy828301@gmail.com> Reviewed-by: Zi Yan <ziy@nvidia.com> Cc: David Hildenbrand <david@redhat.com> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeelb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Commit a5a9230 (fbdev: fbcon: Properly revert changes when vc_resize() failed) started restoring old font data upon failure (of vc_resize()). But it performs so only for user fonts. It means that the "system"/internal fonts are not restored at all. So in result, the very first call to fbcon_do_set_font() performs no restore at all upon failing vc_resize(). This can be reproduced by Syzkaller to crash the system on the next invocation of font_get(). It's rather hard to hit the allocation failure in vc_resize() on the first font_set(), but not impossible. Esp. if fault injection is used to aid the execution/failure. It was demonstrated by Sirius: BUG: unable to handle page fault for address: fffffffffffffff8 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD cb7b067 P4D cb7b067 PUD cb7d067 PMD 0 Oops: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 8007 Comm: poc Not tainted 6.7.0-g9d1694dc91ce #20 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:fbcon_get_font+0x229/0x800 drivers/video/fbdev/core/fbcon.c:2286 Call Trace: <TASK> con_font_get drivers/tty/vt/vt.c:4558 [inline] con_font_op+0x1fc/0xf20 drivers/tty/vt/vt.c:4673 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline] vt_ioctl+0x632/0x2ec0 drivers/tty/vt/vt_ioctl.c:752 tty_ioctl+0x6f8/0x1570 drivers/tty/tty_io.c:2803 vfs_ioctl fs/ioctl.c:51 [inline] ... So restore the font data in any case, not only for user fonts. Note the later 'if' is now protected by 'old_userfont' and not 'old_data' as the latter is always set now. (And it is supposed to be non-NULL. Otherwise we would see the bug above again.) Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org> Fixes: a5a9230 ("fbdev: fbcon: Properly revert changes when vc_resize() failed") Reported-and-tested-by: Ubisectech Sirius <bugreport@ubisectech.com> Cc: Ubisectech Sirius <bugreport@ubisectech.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Helge Deller <deller@gmx.de> Cc: linux-fbdev@vger.kernel.org Cc: dri-devel@lists.freedesktop.org Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20240208114411.14604-1-jirislaby@kernel.org

The code in ocfs2_dio_end_io_write() estimates number of necessary transaction credits using ocfs2_calc_extend_credits(). This however does not take into account that the IO could be arbitrarily large and can contain arbitrary number of extents. Extent tree manipulations do often extend the current transaction but not in all of the cases. For example if we have only single block extents in the tree, ocfs2_mark_extent_written() will end up calling ocfs2_replace_extent_rec() all the time and we will never extend the current transaction and eventually exhaust all the transaction credits if the IO contains many single block extents. Once that happens a WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to this error. This was actually triggered by one of our customers on a heavily fragmented OCFS2 filesystem. To fix the issue make sure the transaction always has enough credits for one extent insert before each call of ocfs2_mark_extent_written(). Heming Zhao said: ------ PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error" PID: xxx TASK: xxxx CPU: 5 COMMAND: "SubmitThread-CA" #0 machine_kexec at ffffffff8c069932 #1 __crash_kexec at ffffffff8c1338fa #2 panic at ffffffff8c1d69b9 #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2] #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2] #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2] #6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2] #7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2] #8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2] #9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2] #10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2] #11 dio_complete at ffffffff8c2b9fa7 #12 do_blockdev_direct_IO at ffffffff8c2bc09f #13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2] #14 generic_file_direct_write at ffffffff8c1dcf14 #15 __generic_file_write_iter at ffffffff8c1dd07b #16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2] #17 aio_write at ffffffff8c2cc72e #18 kmem_cache_alloc at ffffffff8c248dde #19 do_io_submit at ffffffff8c2ccada #20 do_syscall_64 at ffffffff8c004984 #21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba Link: https://lkml.kernel.org/r/20240617095543.6971-1-jack@suse.cz Link: https://lkml.kernel.org/r/20240614145243.8837-1-jack@suse.cz Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io") Signed-off-by: Jan Kara <jack@suse.cz> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Reviewed-by: Heming Zhao <heming.zhao@suse.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

In the TRACE_EVENT(qdisc_reset) NULL dereference occurred from qdisc->dev_queue->dev <NULL> ->name This situation simulated from bunch of veths and Bluetooth disconnection and reconnection. During qdisc initialization, qdisc was being set to noop_queue. In veth_init_queue, the initial tx_num was reduced back to one, causing the qdisc reset to be called with noop, which led to the kernel panic. I've attached the GitHub gist link that C converted syz-execprogram source code and 3 log of reproduced vmcore-dmesg. https://gist.github.com/yskelg/cc64562873ce249cdd0d5a358b77d740 Yeoreum and I use two fuzzing tool simultaneously. One process with syz-executor : https://github.com/google/syzkaller $ ./syz-execprog -executor=./syz-executor -repeat=1 -sandbox=setuid \ -enable=none -collide=false log1 The other process with perf fuzzer: https://github.com/deater/perf_event_tests/tree/master/fuzzer $ perf_event_tests/fuzzer/perf_fuzzer I think this will happen on the kernel version. Linux kernel version +v6.7.10, +v6.8, +v6.9 and it could happen in v6.10. This occurred from 51270d5. I think this patch is absolutely necessary. Previously, It was showing not intended string value of name. I've reproduced 3 time from my fedora 40 Debug Kernel with any other module or patched. version: 6.10.0-0.rc2.20240608gitdc772f8237f9.29.fc41.aarch64+debug [ 5287.164555] veth0_vlan: left promiscuous mode [ 5287.164929] veth1_macvtap: left promiscuous mode [ 5287.164950] veth0_macvtap: left promiscuous mode [ 5287.164983] veth1_vlan: left promiscuous mode [ 5287.165008] veth0_vlan: left promiscuous mode [ 5287.165450] veth1_macvtap: left promiscuous mode [ 5287.165472] veth0_macvtap: left promiscuous mode [ 5287.165502] veth1_vlan: left promiscuous mode … [ 5297.598240] bridge0: port 2(bridge_slave_1) entered blocking state [ 5297.598262] bridge0: port 2(bridge_slave_1) entered forwarding state [ 5297.598296] bridge0: port 1(bridge_slave_0) entered blocking state [ 5297.598313] bridge0: port 1(bridge_slave_0) entered forwarding state [ 5297.616090] 8021q: adding VLAN 0 to HW filter on device bond0 [ 5297.620405] bridge0: port 1(bridge_slave_0) entered disabled state [ 5297.620730] bridge0: port 2(bridge_slave_1) entered disabled state [ 5297.627247] 8021q: adding VLAN 0 to HW filter on device team0 [ 5297.629636] bridge0: port 1(bridge_slave_0) entered blocking state … [ 5298.002798] bridge_slave_0: left promiscuous mode [ 5298.002869] bridge0: port 1(bridge_slave_0) entered disabled state [ 5298.309444] bond0 (unregistering): (slave bond_slave_0): Releasing backup interface [ 5298.315206] bond0 (unregistering): (slave bond_slave_1): Releasing backup interface [ 5298.320207] bond0 (unregistering): Released all slaves [ 5298.354296] hsr_slave_0: left promiscuous mode [ 5298.360750] hsr_slave_1: left promiscuous mode [ 5298.374889] veth1_macvtap: left promiscuous mode [ 5298.374931] veth0_macvtap: left promiscuous mode [ 5298.374988] veth1_vlan: left promiscuous mode [ 5298.375024] veth0_vlan: left promiscuous mode [ 5299.109741] team0 (unregistering): Port device team_slave_1 removed [ 5299.185870] team0 (unregistering): Port device team_slave_0 removed … [ 5300.155443] Bluetooth: hci3: unexpected cc 0x0c03 length: 249 > 1 [ 5300.155724] Bluetooth: hci3: unexpected cc 0x1003 length: 249 > 9 [ 5300.155988] Bluetooth: hci3: unexpected cc 0x1001 length: 249 > 9 …. [ 5301.075531] team0: Port device team_slave_1 added [ 5301.085515] bridge0: port 1(bridge_slave_0) entered blocking state [ 5301.085531] bridge0: port 1(bridge_slave_0) entered disabled state [ 5301.085588] bridge_slave_0: entered allmulticast mode [ 5301.085800] bridge_slave_0: entered promiscuous mode [ 5301.095617] bridge0: port 1(bridge_slave_0) entered blocking state [ 5301.095633] bridge0: port 1(bridge_slave_0) entered disabled state … [ 5301.149734] bond0: (slave bond_slave_0): Enslaving as an active interface with an up link [ 5301.173234] bond0: (slave bond_slave_0): Enslaving as an active interface with an up link [ 5301.180517] bond0: (slave bond_slave_1): Enslaving as an active interface with an up link [ 5301.193481] hsr_slave_0: entered promiscuous mode [ 5301.204425] hsr_slave_1: entered promiscuous mode [ 5301.210172] debugfs: Directory 'hsr0' with parent 'hsr' already present! [ 5301.210185] Cannot create hsr debugfs directory [ 5301.224061] bond0: (slave bond_slave_1): Enslaving as an active interface with an up link [ 5301.246901] bond0: (slave bond_slave_0): Enslaving as an active interface with an up link [ 5301.255934] team0: Port device team_slave_0 added [ 5301.256480] team0: Port device team_slave_1 added [ 5301.256948] team0: Port device team_slave_0 added … [ 5301.435928] hsr_slave_0: entered promiscuous mode [ 5301.446029] hsr_slave_1: entered promiscuous mode [ 5301.455872] debugfs: Directory 'hsr0' with parent 'hsr' already present! [ 5301.455884] Cannot create hsr debugfs directory [ 5301.502664] hsr_slave_0: entered promiscuous mode [ 5301.513675] hsr_slave_1: entered promiscuous mode [ 5301.526155] debugfs: Directory 'hsr0' with parent 'hsr' already present! [ 5301.526164] Cannot create hsr debugfs directory [ 5301.563662] hsr_slave_0: entered promiscuous mode [ 5301.576129] hsr_slave_1: entered promiscuous mode [ 5301.580259] debugfs: Directory 'hsr0' with parent 'hsr' already present! [ 5301.580270] Cannot create hsr debugfs directory [ 5301.590269] 8021q: adding VLAN 0 to HW filter on device bond0 [ 5301.595872] KASAN: null-ptr-deref in range [0x0000000000000130-0x0000000000000137] [ 5301.595877] Mem abort info: [ 5301.595881] ESR = 0x0000000096000006 [ 5301.595885] EC = 0x25: DABT (current EL), IL = 32 bits [ 5301.595889] SET = 0, FnV = 0 [ 5301.595893] EA = 0, S1PTW = 0 [ 5301.595896] FSC = 0x06: level 2 translation fault [ 5301.595900] Data abort info: [ 5301.595903] ISV = 0, ISS = 0x00000006, ISS2 = 0x00000000 [ 5301.595907] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 5301.595911] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 5301.595915] [dfff800000000026] address between user and kernel address ranges [ 5301.595971] Internal error: Oops: 0000000096000006 [#1] SMP … [ 5301.596076] CPU: 2 PID: 102769 Comm: syz-executor.3 Kdump: loaded Tainted: G W ------- --- 6.10.0-0.rc2.20240608gitdc772f8237f9.29.fc41.aarch64+debug #1 [ 5301.596080] Hardware name: VMware, Inc. VMware20,1/VBSA, BIOS VMW201.00V.21805430.BA64.2305221830 05/22/2023 [ 5301.596082] pstate: 01400005 (nzcv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) [ 5301.596085] pc : strnlen+0x40/0x88 [ 5301.596114] lr : trace_event_get_offsets_qdisc_reset+0x6c/0x2b0 [ 5301.596124] sp : ffff8000beef6b40 [ 5301.596126] x29: ffff8000beef6b40 x28: dfff800000000000 x27: 0000000000000001 [ 5301.596131] x26: 6de1800082c62bd0 x25: 1ffff000110aa9e0 x24: ffff800088554f00 [ 5301.596136] x23: ffff800088554ec0 x22: 0000000000000130 x21: 0000000000000140 [ 5301.596140] x20: dfff800000000000 x19: ffff8000beef6c60 x18: ffff7000115106d8 [ 5301.596143] x17: ffff800121bad000 x16: ffff800080020000 x15: 0000000000000006 [ 5301.596147] x14: 0000000000000002 x13: ffff0001f3ed8d14 x12: ffff700017ddeda5 [ 5301.596151] x11: 1ffff00017ddeda4 x10: ffff700017ddeda4 x9 : ffff800082cc5eec [ 5301.596155] x8 : 0000000000000004 x7 : 00000000f1f1f1f1 x6 : 00000000f2f2f200 [ 5301.596158] x5 : 00000000f3f3f3f3 x4 : ffff700017dded80 x3 : 00000000f204f1f1 [ 5301.596162] x2 : 0000000000000026 x1 : 0000000000000000 x0 : 0000000000000130 [ 5301.596166] Call trace: [ 5301.596175] strnlen+0x40/0x88 [ 5301.596179] trace_event_get_offsets_qdisc_reset+0x6c/0x2b0 [ 5301.596182] perf_trace_qdisc_reset+0xb0/0x538 [ 5301.596184] __traceiter_qdisc_reset+0x68/0xc0 [ 5301.596188] qdisc_reset+0x43c/0x5e8 [ 5301.596190] netif_set_real_num_tx_queues+0x288/0x770 [ 5301.596194] veth_init_queues+0xfc/0x130 [veth] [ 5301.596198] veth_newlink+0x45c/0x850 [veth] [ 5301.596202] rtnl_newlink_create+0x2c8/0x798 [ 5301.596205] __rtnl_newlink+0x92c/0xb60 [ 5301.596208] rtnl_newlink+0xd8/0x130 [ 5301.596211] rtnetlink_rcv_msg+0x2e0/0x890 [ 5301.596214] netlink_rcv_skb+0x1c4/0x380 [ 5301.596225] rtnetlink_rcv+0x20/0x38 [ 5301.596227] netlink_unicast+0x3c8/0x640 [ 5301.596231] netlink_sendmsg+0x658/0xa60 [ 5301.596234] __sock_sendmsg+0xd0/0x180 [ 5301.596243] __sys_sendto+0x1c0/0x280 [ 5301.596246] __arm64_sys_sendto+0xc8/0x150 [ 5301.596249] invoke_syscall+0xdc/0x268 [ 5301.596256] el0_svc_common.constprop.0+0x16c/0x240 [ 5301.596259] do_el0_svc+0x48/0x68 [ 5301.596261] el0_svc+0x50/0x188 [ 5301.596265] el0t_64_sync_handler+0x120/0x130 [ 5301.596268] el0t_64_sync+0x194/0x198 [ 5301.596272] Code: eb15001f 54000120 d343fc02 12000801 (38f46842) [ 5301.596285] SMP: stopping secondary CPUs [ 5301.597053] Starting crashdump kernel... [ 5301.597057] Bye! After applying our patch, I didn't find any kernel panic errors. We've found a simple reproducer # echo 1 > /sys/kernel/debug/tracing/events/qdisc/qdisc_reset/enable # ip link add veth0 type veth peer name veth1 Error: Unknown device type. However, without our patch applied, I tested upstream 6.10.0-rc3 kernel using the qdisc_reset event and the ip command on my qemu virtual machine. This 2 commands makes always kernel panic. Linux version: 6.10.0-rc3 [ 0.000000] Linux version 6.10.0-rc3-00164-g44ef20baed8e-dirty (paran@fedora) (gcc (GCC) 14.1.1 20240522 (Red Hat 14.1.1-4), GNU ld version 2.41-34.fc40) #20 SMP PREEMPT Sat Jun 15 16:51:25 KST 2024 Kernel panic message: [ 615.236484] Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP [ 615.237250] Dumping ftrace buffer: [ 615.237679] (ftrace buffer empty) [ 615.238097] Modules linked in: veth crct10dif_ce virtio_gpu virtio_dma_buf drm_shmem_helper drm_kms_helper zynqmp_fpga xilinx_can xilinx_spi xilinx_selectmap xilinx_core xilinx_pr_decoupler versal_fpga uvcvideo uvc videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 videodev videobuf2_common mc usbnet deflate zstd ubifs ubi rcar_canfd rcar_can omap_mailbox ntb_msi_test ntb_hw_epf lattice_sysconfig_spi lattice_sysconfig ice40_spi gpio_xilinx dwmac_altr_socfpga mdio_regmap stmmac_platform stmmac pcs_xpcs dfl_fme_region dfl_fme_mgr dfl_fme_br dfl_afu dfl fpga_region fpga_bridge can can_dev br_netfilter bridge stp llc atl1c ath11k_pci mhi ath11k_ahb ath11k qmi_helpers ath10k_sdio ath10k_pci ath10k_core ath mac80211 libarc4 cfg80211 drm fuse backlight ipv6 Jun 22 02:36:5[3 6k152.62-4sm98k4-0k]v kCePUr:n e1l :P IUDn:a b4le6 8t oC ohmma: nidpl eN oketr nteali nptaedg i6n.g1 0re.0q-urecs3t- 0at0 1v6i4r-tgu4a4le fa2d0dbraeeds0se-dir tyd f#f2f08 615.252376] Hardware name: linux,dummy-virt (DT) [ 615.253220] pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 615.254433] pc : strnlen+0x6c/0xe0 [ 615.255096] lr : trace_event_get_offsets_qdisc_reset+0x94/0x3d0 [ 615.256088] sp : ffff800080b269a0 [ 615.256615] x29: ffff800080b269a0 x28: ffffc070f3f98500 x27: 0000000000000001 [ 615.257831] x26: 0000000000000010 x25: ffffc070f3f98540 x24: ffffc070f619cf60 [ 615.259020] x23: 0000000000000128 x22: 0000000000000138 x21: dfff800000000000 [ 615.260241] x20: ffffc070f631ad00 x19: 0000000000000128 x18: ffffc070f448b800 [ 615.261454] x17: 0000000000000000 x16: 0000000000000001 x15: ffffc070f4ba2a90 [ 615.262635] x14: ffff700010164d73 x13: 1ffff80e1e8d5eb3 x12: 1ffff00010164d72 [ 615.263877] x11: ffff700010164d72 x10: dfff800000000000 x9 : ffffc070e85d6184 [ 615.265047] x8 : ffffc070e4402070 x7 : 000000000000f1f1 x6 : 000000001504a6d3 [ 615.266336] x5 : ffff28ca21122140 x4 : ffffc070f5043ea8 x3 : 0000000000000000 [ 615.267528] x2 : 0000000000000025 x1 : 0000000000000000 x0 : 0000000000000000 [ 615.268747] Call trace: [ 615.269180] strnlen+0x6c/0xe0 [ 615.269767] trace_event_get_offsets_qdisc_reset+0x94/0x3d0 [ 615.270716] trace_event_raw_event_qdisc_reset+0xe8/0x4e8 [ 615.271667] __traceiter_qdisc_reset+0xa0/0x140 [ 615.272499] qdisc_reset+0x554/0x848 [ 615.273134] netif_set_real_num_tx_queues+0x360/0x9a8 [ 615.274050] veth_init_queues+0x110/0x220 [veth] [ 615.275110] veth_newlink+0x538/0xa50 [veth] [ 615.276172] __rtnl_newlink+0x11e4/0x1bc8 [ 615.276944] rtnl_newlink+0xac/0x120 [ 615.277657] rtnetlink_rcv_msg+0x4e4/0x1370 [ 615.278409] netlink_rcv_skb+0x25c/0x4f0 [ 615.279122] rtnetlink_rcv+0x48/0x70 [ 615.279769] netlink_unicast+0x5a8/0x7b8 [ 615.280462] netlink_sendmsg+0xa70/0x1190 Yeoreum and I don't know if the patch we wrote will fix the underlying cause, but we think that priority is to prevent kernel panic happening. So, we're sending this patch. Fixes: 51270d5 ("tracing/net_sched: Fix tracepoints that save qdisc_dev() as a string") Link: https://lore.kernel.org/lkml/20240229143432.273b4871@gandalf.local.home/t/ Cc: netdev@vger.kernel.org Tested-by: Yunseong Kim <yskelg@gmail.com> Signed-off-by: Yunseong Kim <yskelg@gmail.com> Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com> Link: https://lore.kernel.org/r/20240624173320.24945-4-yskelg@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>

The RISC-V kernel already has checks to ensure that memory which would lie outside of the linear mapping is not used. However those checks use memory_limit, which is used to implement the mem= kernel command line option (to limit the total amount of memory, not its address range). When memory is made up of two or more non-contiguous memory banks this check is incorrect. Two changes are made here: - add a call in setup_bootmem() to memblock_cap_memory_range() which will cause any memory which falls outside the linear mapping to be removed from the memory regions. - remove the check in create_linear_mapping_page_table() which was intended to remove memory which is outside the liner mapping based on memory_limit, as it is no longer needed. Note a check for mapping more memory than memory_limit (to implement mem=) is unnecessary because of the existing call to memblock_enforce_memory_limit(). This issue was seen when booting on a SV39 platform with two memory banks: 0x00,80000000 1GiB 0x20,00000000 32GiB This memory range is 158GiB from top to bottom, but the linear mapping is limited to 128GiB, so the lower block of RAM will be mapped at PAGE_OFFSET, and the upper block straddles the top of the linear mapping. This causes the following Oops: [ 0.000000] Linux version 6.10.0-rc2-gd3b8dd5b51dd-dirty (stuart.menefy@codasip.com) (riscv64-codasip-linux-gcc (GCC) 13.2.0, GNU ld (GNU Binutils) 2.41.0.20231213) #20 SMP Sat Jun 22 11:34:22 BST 2024 [ 0.000000] memblock_add: [0x0000000080000000-0x00000000bfffffff] early_init_dt_add_memory_arch+0x4a/0x52 [ 0.000000] memblock_add: [0x0000002000000000-0x00000027ffffffff] early_init_dt_add_memory_arch+0x4a/0x52 ... [ 0.000000] memblock_alloc_try_nid: 23724 bytes align=0x8 nid=-1 from=0x0000000000000000 max_addr=0x0000000000000000 early_init_dt_alloc_memory_arch+0x1e/0x48 [ 0.000000] memblock_reserve: [0x00000027ffff5350-0x00000027ffffaffb] memblock_alloc_range_nid+0xb8/0x132 [ 0.000000] Unable to handle kernel paging request at virtual address fffffffe7fff5350 [ 0.000000] Oops [#1] [ 0.000000] Modules linked in: [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 6.10.0-rc2-gd3b8dd5b51dd-dirty #20 [ 0.000000] Hardware name: codasip,a70x (DT) [ 0.000000] epc : __memset+0x8c/0x104 [ 0.000000] ra : memblock_alloc_try_nid+0x74/0x84 [ 0.000000] epc : ffffffff805e88c8 ra : ffffffff806148f6 sp : ffffffff80e03d50 [ 0.000000] gp : ffffffff80ec4158 tp : ffffffff80e0bec0 t0 : fffffffe7fff52f8 [ 0.000000] t1 : 00000027ffffb000 t2 : 5f6b636f6c626d65 s0 : ffffffff80e03d90 [ 0.000000] s1 : 0000000000005cac a0 : fffffffe7fff5350 a1 : 0000000000000000 [ 0.000000] a2 : 0000000000005cac a3 : fffffffe7fffaff8 a4 : 000000000000002c [ 0.000000] a5 : ffffffff805e88c8 a6 : 0000000000005cac a7 : 0000000000000030 [ 0.000000] s2 : fffffffe7fff5350 s3 : ffffffffffffffff s4 : 0000000000000000 [ 0.000000] s5 : ffffffff8062347e s6 : 0000000000000000 s7 : 0000000000000001 [ 0.000000] s8 : 0000000000002000 s9 : 00000000800226d0 s10: 0000000000000000 [ 0.000000] s11: 0000000000000000 t3 : ffffffff8080a928 t4 : ffffffff8080a928 [ 0.000000] t5 : ffffffff8080a928 t6 : ffffffff8080a940 [ 0.000000] status: 0000000200000100 badaddr: fffffffe7fff5350 cause: 000000000000000f [ 0.000000] [<ffffffff805e88c8>] __memset+0x8c/0x104 [ 0.000000] [<ffffffff8062349c>] early_init_dt_alloc_memory_arch+0x1e/0x48 [ 0.000000] [<ffffffff8043e892>] __unflatten_device_tree+0x52/0x114 [ 0.000000] [<ffffffff8062441e>] unflatten_device_tree+0x9e/0xb8 [ 0.000000] [<ffffffff806046fe>] setup_arch+0xd4/0x5bc [ 0.000000] [<ffffffff806007aa>] start_kernel+0x76/0x81a [ 0.000000] Code: b823 02b2 bc23 02b2 b023 04b2 b423 04b2 b823 04b2 (bc23) 04b2 [ 0.000000] ---[ end trace 0000000000000000 ]--- [ 0.000000] Kernel panic - not syncing: Attempted to kill the idle task! [ 0.000000] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]--- The problem is that memblock (unaware that some physical memory cannot be used) has allocated memory from the top of memory but which is outside the linear mapping region. Signed-off-by: Stuart Menefy <stuart.menefy@codasip.com> Fixes: c99127c ("riscv: Make sure the linear mapping does not use the kernel mapping") Reviewed-by: David McKay <david.mckay@codasip.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20240622114217.2158495-1-stuart.menefy@codasip.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

…s_lock For storing a value to a queue attribute, the queue_attr_store function first freezes the queue (->q_usage_counter(io)) and then acquire ->sysfs_lock. This seems not correct as the usual ordering should be to acquire ->sysfs_lock before freezing the queue. This incorrect ordering causes the following lockdep splat which we are able to reproduce always simply by accessing /sys/kernel/debug file using ls command: [ 57.597146] WARNING: possible circular locking dependency detected [ 57.597154] 6.12.0-10553-gb86545e02e8c #20 Tainted: G W [ 57.597162] ------------------------------------------------------ [ 57.597168] ls/4605 is trying to acquire lock: [ 57.597176] c00000003eb56710 (&mm->mmap_lock){++++}-{4:4}, at: __might_fault+0x58/0xc0 [ 57.597200] but task is already holding lock: [ 57.597207] c0000018e27c6810 (&sb->s_type->i_mutex_key#3){++++}-{4:4}, at: iterate_dir+0x94/0x1d4 [ 57.597226] which lock already depends on the new lock. [ 57.597233] the existing dependency chain (in reverse order) is: [ 57.597241] -> #5 (&sb->s_type->i_mutex_key#3){++++}-{4:4}: [ 57.597255] down_write+0x6c/0x18c [ 57.597264] start_creating+0xb4/0x24c [ 57.597274] debugfs_create_dir+0x2c/0x1e8 [ 57.597283] blk_register_queue+0xec/0x294 [ 57.597292] add_disk_fwnode+0x2e4/0x548 [ 57.597302] brd_alloc+0x2c8/0x338 [ 57.597309] brd_init+0x100/0x178 [ 57.597317] do_one_initcall+0x88/0x3e4 [ 57.597326] kernel_init_freeable+0x3cc/0x6e0 [ 57.597334] kernel_init+0x34/0x1cc [ 57.597342] ret_from_kernel_user_thread+0x14/0x1c [ 57.597350] -> #4 (&q->debugfs_mutex){+.+.}-{4:4}: [ 57.597362] __mutex_lock+0xfc/0x12a0 [ 57.597370] blk_register_queue+0xd4/0x294 [ 57.597379] add_disk_fwnode+0x2e4/0x548 [ 57.597388] brd_alloc+0x2c8/0x338 [ 57.597395] brd_init+0x100/0x178 [ 57.597402] do_one_initcall+0x88/0x3e4 [ 57.597410] kernel_init_freeable+0x3cc/0x6e0 [ 57.597418] kernel_init+0x34/0x1cc [ 57.597426] ret_from_kernel_user_thread+0x14/0x1c [ 57.597434] -> #3 (&q->sysfs_lock){+.+.}-{4:4}: [ 57.597446] __mutex_lock+0xfc/0x12a0 [ 57.597454] queue_attr_store+0x9c/0x110 [ 57.597462] sysfs_kf_write+0x70/0xb0 [ 57.597471] kernfs_fop_write_iter+0x1b0/0x2ac [ 57.597480] vfs_write+0x3dc/0x6e8 [ 57.597488] ksys_write+0x84/0x140 [ 57.597495] system_call_exception+0x130/0x360 [ 57.597504] system_call_common+0x160/0x2c4 [ 57.597516] -> #2 (&q->q_usage_counter(io)#21){++++}-{0:0}: [ 57.597530] __submit_bio+0x5ec/0x828 [ 57.597538] submit_bio_noacct_nocheck+0x1e4/0x4f0 [ 57.597547] iomap_readahead+0x2a0/0x448 [ 57.597556] xfs_vm_readahead+0x28/0x3c [ 57.597564] read_pages+0x88/0x41c [ 57.597571] page_cache_ra_unbounded+0x1ac/0x2d8 [ 57.597580] filemap_get_pages+0x188/0x984 [ 57.597588] filemap_read+0x13c/0x4bc [ 57.597596] xfs_file_buffered_read+0x88/0x17c [ 57.597605] xfs_file_read_iter+0xac/0x158 [ 57.597614] vfs_read+0x2d4/0x3b4 [ 57.597622] ksys_read+0x84/0x144 [ 57.597629] system_call_exception+0x130/0x360 [ 57.597637] system_call_common+0x160/0x2c4 [ 57.597647] -> #1 (mapping.invalidate_lock#2){++++}-{4:4}: [ 57.597661] down_read+0x6c/0x220 [ 57.597669] filemap_fault+0x870/0x100c [ 57.597677] xfs_filemap_fault+0xc4/0x18c [ 57.597684] __do_fault+0x64/0x164 [ 57.597693] __handle_mm_fault+0x1274/0x1dac [ 57.597702] handle_mm_fault+0x248/0x484 [ 57.597711] ___do_page_fault+0x428/0xc0c [ 57.597719] hash__do_page_fault+0x30/0x68 [ 57.597727] do_hash_fault+0x90/0x35c [ 57.597736] data_access_common_virt+0x210/0x220 [ 57.597745] _copy_from_user+0xf8/0x19c [ 57.597754] sel_write_load+0x178/0xd54 [ 57.597762] vfs_write+0x108/0x6e8 [ 57.597769] ksys_write+0x84/0x140 [ 57.597777] system_call_exception+0x130/0x360 [ 57.597785] system_call_common+0x160/0x2c4 [ 57.597794] -> #0 (&mm->mmap_lock){++++}-{4:4}: [ 57.597806] __lock_acquire+0x17cc/0x2330 [ 57.597814] lock_acquire+0x138/0x400 [ 57.597822] __might_fault+0x7c/0xc0 [ 57.597830] filldir64+0xe8/0x390 [ 57.597839] dcache_readdir+0x80/0x2d4 [ 57.597846] iterate_dir+0xd8/0x1d4 [ 57.597855] sys_getdents64+0x88/0x2d4 [ 57.597864] system_call_exception+0x130/0x360 [ 57.597872] system_call_common+0x160/0x2c4 [ 57.597881] other info that might help us debug this: [ 57.597888] Chain exists of: &mm->mmap_lock --> &q->debugfs_mutex --> &sb->s_type->i_mutex_key#3 [ 57.597905] Possible unsafe locking scenario: [ 57.597911] CPU0 CPU1 [ 57.597917] ---- ---- [ 57.597922] rlock(&sb->s_type->i_mutex_key#3); [ 57.597932] lock(&q->debugfs_mutex); [ 57.597940] lock(&sb->s_type->i_mutex_key#3); [ 57.597950] rlock(&mm->mmap_lock); [ 57.597958] *** DEADLOCK *** [ 57.597965] 2 locks held by ls/4605: [ 57.597971] #0: c0000000137c12f8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0xcc/0x154 [ 57.597989] #1: c0000018e27c6810 (&sb->s_type->i_mutex_key#3){++++}-{4:4}, at: iterate_dir+0x94/0x1d4 Prevent the above lockdep warning by acquiring ->sysfs_lock before freezing the queue while storing a queue attribute in queue_attr_store function. Later, we also found[1] another function __blk_mq_update_nr_ hw_queues where we first freeze queue and then acquire the ->sysfs_lock. So we've also updated lock ordering in __blk_mq_update_nr_hw_queues function and ensured that in all code paths we follow the correct lock ordering i.e. acquire ->sysfs_lock before freezing the queue. [1] https://lore.kernel.org/all/CAFj5m9Ke8+EHKQBs_Nk6hqd=LGXtk4mUxZUN5==ZcCjnZSBwHw@mail.gmail.com/ Reported-by: kjain@linux.ibm.com Fixes: af28141 ("block: freeze the queue in queue_attr_store") Tested-by: kjain@linux.ibm.com Cc: hch@lst.de Cc: axboe@kernel.dk Cc: ritesh.list@gmail.com Cc: ming.lei@redhat.com Cc: gjoyce@linux.ibm.com Signed-off-by: Nilay Shroff <nilay@linux.ibm.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Link: https://lore.kernel.org/r/20241210144222.1066229-1-nilay@linux.ibm.com Signed-off-by: Jens Axboe <axboe@kernel.dk>

--author MIZZ122<liaiai@hikdata.com>

39a8319

-m tracker.ceph.com/issues/25150

idryomov closed this Oct 12, 2018

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Failed to write data to rbd device even removed from blacklist#20

Failed to write data to rbd device even removed from blacklist#20
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MIZZ122 commented Aug 15, 2018

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MIZZ122 commented Aug 15, 2018

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idryomov commented Oct 12, 2018

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